U.S. President Donald Trump said on Tuesday he will "probably" meet Russian President Vladimir Putin this month, a suggestion the Kremlin confirmed briefly after U.S. and Russian delegations held talks on ending the Ukraine conflict.

Dismissing Ukraine's concern about being left out of the talks in Riyadh, Trump noted during a press conference at his Mar-a-Lago estate in Florida that Ukraine could have made a deal with Russia three years ago.

"Today I heard, 'Oh, we weren't invited.' Well, you've been there for three years; you should have ended it ... you should have never started it. You could have made a deal," said Trump, referring to Ukrainian President Volodymyr Zelenskyy.

The U.S. president's remarks were the harshest criticism of Zelenskyy to date, signaling a departure from the previous U.S. policy on the Russian-Ukrainian conflict.

He also derided Zelenskyy as an inadequate negotiator and "grossly incompetent."

Kremlin spokesperson Dmitry Peskov said the U.S.-Russia talks in Riyadh were a "very, very important step" towards reaching a settlement on the Ukraine conflict.

"In order to carry out, figuratively speaking, resuscitation measures, diplomats will now begin to work in light of the agreement (Russian Foreign Minister Sergey) Lavrov reached yesterday with (U.S. Secretary of State Marco) Rubio," Peskov was quoted by Russian state media as saying.

"But this is the first step ... Naturally, it's impossible to fix everything in one day or a week. There is a long way to go," he added.

Trump also said he would not oppose stationing European peacekeeping troops in Ukraine.

"Having troops over there would be fine; I wouldn't object to it at all," he said. However, he indicated that the United States would not participate "because we're very far away."

Earlier on Tuesday, U.S. Secretary of State Marco Rubio announced that the United States and Russia reached an agreement on four principles after extensive talks in Saudi Arabia, including the establishment of a high-level team to help "negotiate and work through the end of the conflict in Ukraine in a way that's enduring and acceptable to all the parties engaged."

The meeting in Saudi Arabia is the latest indication of a thaw in the previously frosty relations between Washington and Moscow since Trump took office in January.

Zelenskyy, who said any peace negotiations between Russia and his country can't proceed without "certain security guarantees," has cancelled his scheduled visit to Saudi Arabia following the U.S.-Russian talks, citing his intent to avoid "coincidences."

"We are completely honest and open. That's why I don't want any 'coincidences.' That's why I won't go to Saudi Arabia," Zelenskyy told reporters during his visit to Ankara.

(With input from agencies)