U.S. President Donald Trump's comments this week claiming Ukraine was responsible for starting the three-year conflict with Russia and calling Ukrainian President Volodymyr Zelenskyy "a dictator without elections" drew criticism from congressional Democrats and pushback from some members of the Republican Party.

"Clearly, Vladimir Putin is responsible for this war," Republican Senator Thom Tillis told reporters. "His decision has resulted in the murder, rape, torture and kidnapping of untold numbers of Ukrainians. He owns responsibility for this war. I don't know how more plainly it can be stated."

Republican Senator John Kennedy told reporters he believes Russia started the war.

"I also believe, through bitter experience, that Vladimir Putin is a gangster. He's a gangster with a black heart," he added.

But Senate Majority Leader John Thune declined to criticize Trump when speaking to reporters Wednesday.

"The president speaks for himself," Thune said. "What I want to see is a peaceful result, a peaceful outcome. And I think right now, there's a negotiation going on, and let's see where that ultimately leads."

Republican Senator Josh Hawley said Trump has blamed Russia "as well, and threatened to sanction Russia if they didn't come to the negotiating table."

The conflict between Trump and Zelenskyy comes as U.S. envoy Keith Kellogg arrived in Kyiv on Wednesday to meet with Zelenskyy.

Ukraine was not included in peace talks that began this week in Riyadh, Saudi Arabia, between the United States and Russia. Trump brushed off Ukraine's complaints at not being included in negotiations, saying Tuesday, "You never should have started it."

Russia invaded Ukraine on Feb. 24, 2022, claiming eastern parts of the country needed to be liberated. U.S. officials say nearly half a million Ukrainian civilians have died in the war and at least 124,000 Ukrainian soldiers.

After Trump's comment, seeming to blame the Ukrainian leader for starting the war, Zelenskyy responded on social media that Trump lives in a "disinformation space" influenced by Russia.

Trump responded to Zelenskyy on Truth Social on Wednesday: "Think of it, a modestly successful comedian, Volodymyr Zelenskyy, talked the United States of America into spending $350 Billion Dollars, to go into a War that couldn't be won, that never had to start, but a War that he, without the U.S. and 'TRUMP,' will never be able to settle. A Dictator without Elections, Zelenskyy better move fast or he is not going to have a Country left."

Hawley told reporters Wednesday that he supported Trump's calls for an election in Ukraine.

"The suspension of elections in Ukraine is a bad deal," Hawley said. "Zelenskyy should hold elections. He's the elected leader of the country. Our president is right — they haven't had elections in a long time, and they are basically under martial law. That's not good when you claim to be defending democracy. You need to practice it."

But Democrats said Trump's comments endanger America's standing on the global stage.

"This is outrageous. It's outrageous if not humorous that the president does these sorts of things, goes off on wild tangents and says things that are clearly false," Senate Minority Whip Dick Durbin told reporters.

Democratic Senator Elissa Slotkin said Wednesday, "It is what we all feared, which is he understands incorrectly what's happening in the span of history and is blaming the head of a country that has been invaded by an autocratic regime; a democracy was invaded.

"And however you want to solve it, however you want to negotiate, is one thing," Slotkin said. "But he put down his cards."

VOA's Kateryna Lisunova contributed to this report.