US President Donald Trump on Monday said Ukrainian leader Volodymyr Zelenskyy could “end the war with Russia almost immediately, if he wants to,” as the two prepared to meet in Washington.

In a string of Truth Social posts, Trump declared that Ukraine must abandon its NATO ambitions and accept that Crimea—seized by Moscow in 2014 under Barack Obama’s presidency—would not be returned. “President Zelenskyy can end the war almost immediately, or continue to fight. Remember how it started. No getting back Obama-given Crimea (12 years ago, without a shot being fired!), and no going into Nato. Some things never change!” Trump wrote.

He added that Tuesday would mark “a big day at the White House,” with several top European leaders expected. “Never had so many European leaders at one time. My great honour to host them!!!” he posted, dismissing media suggestions that the gathering was a setback. “Actually, it is a great honour for America!!!”

Zelenskyy, arriving in Washington, said he was “grateful” for Trump’s invitation but insisted peace must be “lasting, not like years ago, when Ukraine was forced to give up Crimea and part of Donbas.” He reiterated that “Russia must end this war, which it started,” expressing confidence that with U.S. and European backing, Moscow could be pushed toward a “real peace.”

Among those joining Zelenskyy are European Commission chief Ursula von der Leyen, French President Emmanuel Macron, Italian Prime Minister Giorgia Meloni, German Chancellor Friedrich Merz, NATO Secretary-General Mark Rutte, and UK Prime Minister Keir Starmer.

The gathering comes days after Trump’s nearly three-hour meeting with Russian President Vladimir Putin in Alaska, where the two discussed a potential deal. Trump later said it was up to Zelenskyy to “secure a deal and bring the war to an end.”

Tensions remain high after Trump’s February Oval Office meeting with Zelenskyy, which spiraled into a televised clash. Trump accused Kyiv of dragging out the conflict and warned he might withdraw U.S. support, sparking weeks of bitter exchanges.

Now, with European and NATO leaders rallying in Washington, the spotlight shifts to whether Zelenskyy and Trump can avoid another confrontation—and whether peace will come on Ukraine’s terms or Moscow’s.