President Donald Trump announced Wednesday he and Russia’s leader agreed in a phone call to “immediately” begin negotiations with Ukraine’s leader to bring an end to the nearly three-year-conflict.

“We will begin by calling President Zelenskyy, of Ukraine, to inform him of the conversation, something which I will be doing right now,” Trump said on his social media platform Truth Social. “I have asked Secretary of State Marco Rubio, Director of the CIA John Ratcliffe, National Security Advisor Michael Waltz, and Ambassador and Special Envoy Steve Witkoff, to lead the negotiations which, I feel strongly, will be successful.”

Trump did not specify what the terms might be to end the Russia-Ukraine conflict. But Secretary of Defense Pete Hegseth, in Germany Wednesday for a meeting of the Ukraine Defense Contact Group, ruled out a key demand by Ukraine: eventual membership in NATO.

“The United States does not believe that NATO membership for Ukraine is a realistic outcome of a negotiated settlement,” Hegseth said.

Trump’s top hostage negotiator on Wednesday credited Trump’s “great friendship” with Russia’s leader and with Saudi Arabia’s prince as key in releasing American teacher Marc Fogel from Russian custody late Tuesday.

“I think that getting Marc Fogel out was critical and the Russians were very, very helpful in that effort and very accommodating,” Witkoff said, speaking to reporters at the White House. “And I think that's maybe a sign about how that working relationship between President Trump and President Putin will be in the future and what that may portend for the world at large for conflict and so forth. I think they had a great friendship. And I think now it's going to continue and it's a really good thing for the world.”

Trump welcomed Fogel to the White House late Tuesday. He had been detained since August 2021 for bringing medically prescribed marijuana into the country.

“I feel like the luckiest man on Earth right now,” Fogel said as he stood next to Trump at the White House late Tuesday.

Trump said he appreciated what Russia did in letting Fogel go home but declined to specify the details of any agreement with Russia beyond calling it “very fair” and very reasonable.”

Trump also said another hostage release would be announced Wednesday.

Waltz, Trump’s national security adviser, said earlier Tuesday the United States and Russia “negotiated an exchange” to free Fogel but gave no details about what the U.S. side of the bargain entailed. In such deals in recent years, the U.S has often released Russian prisoners that Moscow wanted in exchange.

Instead, Waltz cast the deal for Fogel’s release in broader geopolitical terms, saying it was “a show of good faith from the Russians and a sign we are moving in the right direction to end the brutal and terrible war in Ukraine,” an invasion Russia launched against its neighbor in February 2022, with hundreds of thousands killed or wounded on both sides.

Trump had vowed to broker an end to Russia’s war on Ukraine before taking office January 20, but his aides more recently have said he hopes to do it within the first 100 days of his new administration, roughly by the end of April.

“Since President Trump’s swearing-in, he has successfully secured the release of Americans detained around the world, and President Trump will continue until all Americans being held are returned to the United States,” Waltz said. The recent release of six Americans held in Venezuela and Fogel’s freeing are the only publicly known instances.

Fogel had been traveling with a small amount of medically prescribed marijuana to treat back pain. Once convicted by a Russian court, he began serving his 14-year sentence in June 2022, with the outgoing administration of former President Joe Biden late last year classifying him as wrongfully detained.