On the first day of Russia’s all-out invasion, President Volodymyr Zelensky of Ukraine and his main political opponent at home shook hands, setting aside their ferocious rivalry to focus on the enemy. The country’s typically raucous politics went largely dormant for the three years that followed.

Now, as peace talks led by the Trump administration have stirred prospects for a cease-fire and eventual elections, the political jockeying has returned.

Ukrainian politicians are maneuvering at home and reaching out behind the scenes to the Trump administration, which has made no secret of its disdain for Mr. Zelensky, despite his lionization on the world stage for standing up to Russia.

Petro O. Poroshenko, a former Ukrainian president and the leader of a rival party, says that the best way to smooth the peace talks is to bring opposition figures into the government.

Mr. Poroshenko had earlier floated the idea of overhauling Ukraine’s politics to form a national unity government, which could benefit his party. He revived the proposal after Mr. Zelensky’s contentious Oval Office meeting with President Trump in February and a call by a Republican senator for him to step down.

Mr. Zelensky has shown no interest in forming a coalition of ministers that would include opposition figures. Instead, his government has ratcheted up pressure on opponents by law enforcement and security agencies.

The mayor of Kyiv, Vitali Klitschko, has said Mr. Zelensky abused martial law powers to overrule the city council. In January, Ukraine’s national security council froze Mr. Poroshenko’s bank accounts while leveling no specific accusations.

“We don’t have any other option other than a coalition of national unity, a government of national unity,” Mr. Poroshenko said in an interview on Wednesday. “We should have unity in the Parliament and demonstrate unity in the country. And the results of this decision should be a stop to the war.”

Mr. Zelensky’s five-year term, which was set to expire last year, was extended under martial law. Elections are legally banned under martial law and impractical as long as Ukraine remains at war.

Nearly a month ago, Ukraine offered a monthlong, unconditional cease-fire that Russia has not accepted. A Trump administration envoy, Steve Witkoff, traveled to Russia on Friday, possibly in an effort to rekindle negotiations.

Mr. Poroshenko said that the talks could get a boost if Mr. Zelensky allowed political opponents to enter the government, given that Mr. Trump has called Mr. Zelensky a “dictator without elections.” That echoed criticism by the Russian president, Vladimir V. Putin, who has said he will not sign a peace settlement with Mr. Zelensky.

Mr. Poroshenko said he disagreed with Mr. Trump’s assessment of Mr. Zelensky as a dictator.

But with the prospect of a cease-fire and elections, Mr. Poroshenko has taken to more openly criticizing the president. The sanctions that the national security council placed on Mr. Poroshenko froze his bank accounts and could exclude him from future elections.

Mr. Poroshenko called the sanctions against him “disastrous, unconstitutional and extrajudicial.” If he were arrested, he said, he would then say that Ukraine is on a path to dictatorship.

The intense rivalry between the two Ukrainian leaders goes back years. Mr. Poroshenko led Ukraine from 2014 to 2019. After Mr. Zelensky soundly defeated him, the new government then questioned Mr. Poroshenko as a witness in a flurry of criminal cases that Mr. Poroshenko called politically motivated.

Even as tanks massed at the border before Russia invaded in 2022, the infighting continued in Ukraine: Prosecutors sought an arrest warrant for Mr. Poroshenko, though it was declined by a judge.

Mr. Poroshenko has a base of support in Ukrainian nationalist politics, particularly in western and central Ukraine, while Mr. Zelensky in the 2019 race won broad support across the country, including from Russian speakers in central and eastern Ukraine.

The two men met on the morning of Feb. 24, 2022, when Russia began its onslaught, to set aside their rivalry. Mr. Zelensky asked what he could do for Mr. Poroshenko. The former president said that he asked for 5,000 Kalashnikovs to arm his supporters against the Russians, and that Mr. Zelensky had provided the guns.

Mr. Poroshenko, 59, has little chance of winning a presidential election, polls show. He has consistently been in third place or lower, behind Mr. Zelensky and a former army commander, Gen. Valery Zaluzhny.

Political analysts say that Mr. Poroshenko may be angling for an electoral alliance with General Zaluzhny, who is serving as ambassador to Britain and is wildly popular in Ukraine. He has remained mostly silent about politics.

In the interview, Mr. Poroshenko said he had met with Mr. Zaluzhny in London, but he declined to disclose details of their talks. An aide to Mr. Poroshenko said he had accepted an autographed copy of the general’s biography, “Iron General.”

As Mr. Zelensky has negotiated with the Trump administration, Mr. Poroshenko has offered advice through intermediaries, he said.

“Trump can ask unexpected questions, I can say even impolite,” Mr. Poroshenko said.

At one meeting during the first Trump administration, Mr. Poroshenko said, Mr. Trump asked if he could get an honest answer to a question. Mr. Poroshenko said yes. Mr. Trump then leaned closer and asked, “‘Tell me, is Crimea Russian?’”

Mr. Poroshenko said he answered that Crimea, the peninsula that Russia seized in 2014, was Ukrainian, and asked what prompted the question. Mr. Trump then said that a Russian friend had told him that the peninsula should be Russian, Mr. Poroshenko said.

Mr. Poroshenko pursued a transactional foreign policy with the United States that partly paid off. That included purchases of coal from Pennsylvania that preserved some jobs in a swing state, even though Ukraine has abundant coal of its own.

Before the end of Mr. Trump’s first term, the administration offered a formal statement, known as the Crimea Declaration, that asserted as a matter of U.S. policy that Crimea was Ukrainian.

“He’s not easy,” Mr. Poroshenko said of Mr. Trump. “But now is the time of diplomacy.”

Secretary of State Marco Rubio said on Sunday that the United States had sent 10 members of two gangs — MS-13, which originated in the United States and operates in South America, and Tren de Aragua, rooted in Venezuela — to El Salvador late Saturday.

Mr. Rubio added in a social media post that “the alliance” between President Trump and President Nayib Bukele of El Salvador had “become an example for security and prosperity in our hemisphere.”

The Trump administration has sent hundreds of Venezuelans to a notorious prison in El Salvador at the invitation of Mr. Bukele, who is positioning himself as a crucial regional ally to Mr. Trump and is scheduled to meet with the president in Washington on Monday.

The administration has portrayed those deportees as violent criminals or terrorists, but court papers have shown that the evidence on which the government acted was often little more than whether they had tattoos or had worn clothing associated with the criminal organization.

Mr. Bukele has become Latin America’s most popular leader for his takedown of gangs, even as he has suspended civil liberties and been accused by U.S. prosecutors of secretly negotiating with the same gangs.

A spokeswoman for Mr. Bukele, Wendy Ramos, did not immediately respond to a request for information on the 10 deportees Mr. Rubio referred to.

In early February, Mr. Rubio announced a possible deal with Mr. Bukele, under which the Salvadoran government would hold convicted criminals in its prison system, for a fee. The administration began sending groups of detainees to El Salvador in mid-March, and has so far sent at least five flights carrying Venezuelan and Salvadoran deportees to El Salvador.

The Salvadoran government has released videos and photos showing deportees being removed from planes and marched into a prison outside the capital, San Salvador, called the Terrorism Confinement Center, or CECOT.

Some of the men have been removed from the United States under the Alien Enemies Act, a wartime power dating to 1798, while others were removed under regular U.S. immigration law and had final deportation orders, according to the administration.

The Supreme Court ruled last week that the Trump administration could continue to deport Venezuelan migrants using the Alien Enemies Act for now, overturning a lower court that had put a temporary stop to those deportations.

The decision represented a victory for the administration, though the ruling did not address the constitutionality of using the Alien Enemies Act to send the migrants to a prison in El Salvador. The justices instead issued a narrow procedural ruling, saying that the migrants’ lawyers had filed their lawsuit in the wrong court.

In a separate case, the Supreme Court ordered the administration on Thursday to take steps to return a Salvadoran man, Kilmar Armando Abrego Garcia, who was legally in the United States but was sent to the prison in El Salvador in March as a result of what officials said was an administrative error. But the administration has defied an order by the federal judge handling Mr. Abrego Garcia’s case to provide a written road map of its plans to free him, and in a hearing on Friday, repeatedly stonewalled the judge’s efforts to get the most basic information about him.

On Saturday, a State Department official, Michael Kozak, told the Maryland judge in Mr. Abrego Garcia’s case that the detainee was “alive and secure” and that, according to the U.S. Embassy in San Salvador, he was in being held in CECOT. The embassy has not responded to requests for information from The New York Times.

Following the Supreme Court’s order on Thursday, President Trump said that he would follow the directions of the court if it ordered him to “bring somebody back,” though the court’s ruling indicated that the judiciary might not have the power to require the executive branch to do so.

On Saturday, Mr. Trump wrote of the deportees on Truth Social: “These barbarians are now in the sole custody of El Salvador, a proud and sovereign Nation. And their future is up to President B and his Government.”

President Bukele, who posted a photo on social media that day indicating that he was on his way to Washington, has largely remained silent on Mr. Abrego Garcia’s case.

Eric Schmitt reported from Washington and Annie Correal from Panama City.

The first meeting between the United States and Iran over its expanding nuclear program on Saturday displayed a seriousness of purpose and an effort to avoid what neither side wants, another war in the Middle East. They will talk again next Saturday, but the hard work lies ahead, as hard-liners in both countries, and Israel, are expected to balk at most any deal.

If the first nuclear deal, reached in 2015, was prompted by Iran’s desire to rid itself of punishing economic sanctions, these talks have more urgency. Iran, battered by Israel and with its regional proxies diminished, still wants economic relief. But it also understands that the Islamic Republic itself is under threat and that President Trump, who pulled out of the first deal because he thought it was too weak, may not be bluffing about Iran’s facing “bombing the likes of which they’ve never seen before.”

And Iran’s supreme leader, Ayatollah Ali Khamenei, has given his negotiators at least one last chance to trade Iran’s nuclear ambitions for lasting security.

The talks in Oman also promised some efficiency. The 2015 deal was struck between Iran and six countries — the five permanent members of the United Nations Security Council plus Germany, with the European Union playing the role of intermediary — and took two years.

This time the talks are bilateral, with the Europeans but also Russia and China on the sidelines. And although the United States remains “the Great Satan” for Ayatollah Khamenei, it also holds the key to restraining Israel and securing any lasting settlement. While Iran insisted on indirect talks through Oman, and Mr. Trump on direct talks, the two sides managed to fudge the issue, with Mr. Trump’s special envoy, Steve Witkoff, talking directly to Iran’s foreign minister, Abbas Araghchi, as the meeting ended.

“This is as good a start as it gets,” said Ali Vaez, Iran project director for the International Crisis Group. “They could have stumbled, but they agreed to meet again, they met together at the end and they agreed on the ultimate objective.”

Importantly, Mr. Trump and Mr. Witkoff indicated that their real bottom line is ensuring that Iran can never build a nuclear weapon — despite harsh demands from Trump officials before the talks that Iran dismantle its nuclear program entirely as well as abandon its missile program and its support for its regional proxies.

Iran had made it clear that such broad demands would leave it defenseless and would end the talks before they began. So limiting the goal to ensuring that Iran can never build a nuclear bomb, if the administration sticks with that, would sharply enhance the talks’ chance of success.

“The Iranians came prepared for more than an icebreaker, but with the expectation to break the logjam with the U.S., and most important, to hear directly what is the real U.S. bottom line,” said Vali Nasr, a professor at the Johns Hopkins School of Advanced International Studies. “If it’s no weapon, then they can negotiate on levels of enrichment, inspections and so on. But Iran does not want to get into a situation where it cannot deliver and risk more sanctions and war,” he said. “What Iran wants is pretty clear: credible sanction relief and a deal that sticks.”

Iran insists that its nuclear program is solely civilian, but it has enriched enough uranium close to weapons-grade quality to make at least six bombs, according to data from the International Atomic Energy Agency, which implements the Nuclear Nonproliferation Treaty that Iran has signed.

Despite their mistrust of Mr. Trump, the Iranians think he would be better able to guarantee the sustainability of a deal that he makes and face down his own Republican hard-liners, Mr. Nasr said. The Iranians never trusted President Joseph R. Biden Jr. “to follow through and avoid being undermined by Congress,” he said.

“We’re in the best place we could be after this meeting,” said Sanam Vakil, director of the Middle East and North Africa Program at Chatham House. There were positive statements from both sides around a plan to move forward, she said, and “a mutual understanding about the urgency required, the opportunity presented and signs of pragmatism from both sides.”

The she added, “Of course, the hard stuff lies ahead.”

A serious deal will be enormously complicated and technical, and it will take time. It would also need to survive efforts to undermine the talks by hard-liners in both countries and in Israel. Israel, which opposed the 2015 deal, wants a more comprehensive disarmament of Iran and keeps talking about the need to strike it militarily now, when the regime is weak and its air defenses have been badly compromised by Israeli airstrikes.

Iran has in the past vowed to destroy Israel, and Prime Minister Benjamin Netanyahu of Israel says he wants Iran to no longer be able to enrich any uranium at all. Israel, citing the Hamas attack in Gaza, has badly damaged Iranian proxies, including Hamas and Hezbollah in Lebanon, and wants to try to ensure that Iran cannot rebuild them.

But Iran may also be encouraged that Mr. Trump announced the talks in the Oval Office next to Mr. Netanyahu, who did not look or sound very pleased about them. Iran will see “a powerful signal from Trump that he’s not owned by Netanyahu,” Mr. Nasr said.

The hope is that a next meeting or two can produce an interim agreement that gives both sides confidence to move forward, with short-term measures from both sides so long as the talks continue. They could include Iran’s agreeing to freeze uranium enrichment and allow more inspections in return for Washington’s suspending some of its “maximum pressure” sanctions.

Iran is likely to insist on a step-by-step process that could take several years, Mr. Nasr said, “to help the deal grow roots before someone else comes into office and tried to undo it.” A longer process would also provide more security for Iran.

Still, Iran has no reason to stretch out the talks themselves. “Iran’s leverage is its nuclear enrichment, and more time won’t give them more leverage,” Mr. Vaez said. And then there is “the ticking time bomb of the snapback sanctions.”

Those sanctions, suspended under the 2015 deal, can be restored if any signatory — in this case, the Europeans — decides that there is no new deal or significant progress toward one. But that must happen before Oct. 18, when the ability to “snap back” expires. Officials say that the Europeans are exploring whether that deadline can be delayed, but the mechanism to do that is unclear.

In any case, the analysts agree, Iran does not want to be blamed for the failure of these talks. If they do fail and war ensues, the regime wants to be able to blame American perfidy and bad faith.

So if a deal can be done, Iran will want guarantees this time that it will be durable and deliver commercial engagement in a meaningful and long-term way, Ms. Vakil said. Iran will want to know “how Trump can guarantee protection that other presidents have been unable to do.”

And the United States, she said, will want to know what guarantees Iran can provide for the security of Israel and the stability of the larger Middle East.

“A deal must be mutually beneficial, but it requires a lot of trust and accountability along the way that both sides simply don’t have right now,” she said.

The governor of Pennsylvania, Josh Shapiro, said he and his family were evacuated from their home early on Sunday after an arson attack that significantly damaged a section of the governor’s official residence.

Mr. Shapiro, a Democrat, said on social media that the Pennsylvania State Police woke his family by banging on the door around 2 a.m. to warn them of the fire. He said no one was injured.

The State Police and the Pennsylvania Capitol Police evacuated his family while firefighters extinguished the fire, the governor said.

“Every day, we stand with the law enforcement and first responders who run towards danger to protect our communities,” the governor said. “Last night, they did so for our family — and Lori and I are eternally grateful to them for keeping us safe.”

The State Police said in a statement that the fire caused “a significant amount of damage to a portion of the residence.”

The police did not identify a suspect and said an investigation was underway.

Hours before the fire, Mr. Shapiro wrote on social media that he and his family were marking Passover, which began at sunset on Saturday.

Images posted on social media showed firefighters battling the fire. A portion of the mansion was obscured in dark smoke, and some windows were shattered.

Mr. Shapiro, a Democrat, gained national prominence last year when he was on the short list of possible running mates for Vice President Kamala Harris on the Democratic presidential ticket. She eventually chose Gov. Tim Walz of Minnesota.

Mr. Shapiro’s nearly two decades in public office includes six years as the state’s attorney general. He was elected governor in 2022.

The governor’s residence is a 29,000-square-foot Georgian-style home on the Susquehanna River, according to the state government. Its landscaped grounds occupy a full block about a mile and a half from the State Capitol complex. Eight governors have lived there with their families since it was completed in 1968.

The public is able to tour the residence, which exhibits art and artifacts on the first floor.

A renovation of the property was completed in 2022 to make it more accessible to people with mobility issues and more environmentally friendly, The Patriot-News reported.

This is a developing story. Check back for updates.