President Volodymyr Zelensky accused Vladimir Putin on Friday of sabotaging diplomatic efforts to secure peace in Ukraine over the Russian leader's response to a US-Ukrainian proposal for an unconditional 30-day ceasefire.
"He is now doing everything he can to sabotage diplomacy by setting extremely difficult and unacceptable conditions right from the start even before a ceasefire," Zelensky said in a post on X.
Washington and Kyiv have been pushing for an immediate 30-day truce, but Putin has expressed doubt over the plan, saying important questions remain.
Zelensky said the United States could exert sufficient pressure on Russia to stop its invasion because, he said, Putin "will not end the war on his own".
"The strength of America is enough to make it happen. Strong steps are needed. Strong pressure must be applied to the only one who wants to continue this war," Zelensky said in a statement on social media.
Kyiv has, throughout the war, relied on support from Washington, which has been its most important military and political ally.
Trump, however, initiated a reversal in US policy by reaching out to Russia and temporarily halting military assistance to Ukraine, even clashing with Zelensky at the White House.
After Ukraine endorsed the American proposal for a 30-day ceasefire with Moscow in talks in the Saudi port of Jeddah last week, Trump lifted the freeze.
Zelensky, who has praised the talks in Jeddah, said it was important to "preserve dialogue" between the United States and Ukraine.
He also said Ukraine needed to maintain effective ties with Trump during a meeting with journalists in Kyiv.
"Close relations with the United States are very important for Ukraine. I represent Ukraine as its president. America is represented by Donald Trump, as the duly elected president. We need normal, functional relations," he said.