U.S. President Donald Trump has sharply criticized Ukrainian President Volodymyr Zelensky, accusing him of jeopardizing a potential peace agreement with Russia by refusing to recognize Moscow’s occupation of Crimea.

In a post on social media, Trump called Zelensky’s recent remarks “inflammatory,” claiming they would make negotiations “much harder” and delay an end to the war. “That statement is very damaging to the peace process with Russia,” Trump wrote.

He argued that Crimea had been effectively lost “many years ago” and insisted that a peace deal was now within reach. “He has nothing to brag about,” Trump said of Zelensky. “Ukraine is in a dire situation — he can choose peace now or keep fighting for three more years and risk losing the entire country.”

U.S. Vice President JD Vance echoed Trump’s stance, saying the time had come for both Ukraine and Russia to accept America’s peace proposal or for the U.S. to step away from the negotiations entirely.

Tensions around the diplomatic process intensified after a planned Ukraine peace summit in London was suddenly scaled back. The meeting, set for Wednesday, lost momentum after U.S. Secretary of State Marco Rubio declined to attend, citing “scheduling conflicts.”

Following Rubio’s withdrawal, foreign ministers from France and Germany also canceled their participation, dealing another blow to the already fragile effort to broker an end to the conflict.