U.S. President Donald Trump ratcheted up pressure on Volodymyr Zelenskyy to accept a peace deal that critics fear will favor Moscow, accusing the Ukrainian president of prolonging the war that’s now in its fourth year.

"I think we have a deal with Russia. We have to get a deal with Zelenskyy. I hope that Zelenskyy — I thought it might be easier to deal with Zelenskyy. So far, it’s been harder,” Trump said Wednesday in the Oval Office.

The comments came hours after the American president posted a broadside against Zelenskyy on his social media platform, and as Ukraine and its European allies have sought to slow Trump’s rush to a deal over worries that it will sacrifice Ukrainian and European security. They insist that a ceasefire and clarity over security guarantees for Ukraine must precede any deal that involves negotiations over territory, according to people familiar with the matter.