US President Donald Trump warned Vladimir Putin Tuesday that he was ?playing with fire,? in a fresh jab at his Russian counterpart as he weighs new sanctions against Moscow over the war in Ukraine.

Trump?s latest broadside showed his frustration with stalled peace talks, and comes two days after he called the Kremlin leader ?absolutely CRAZY? following a record Russian drone attack on Ukraine.

?What Vladimir Putin doesn?t realize is that if it weren?t for me, lots of really bad things would have already happened to Russia, and I mean REALLY BAD. He?s playing with fire!? Trump said on his Truth Social network.

Trump did not specify what the ?really bad? things were, or make any specific threats. The White House did not immediately respond to a request for comment by AFP.

But the Wall Street Journal and CNN both reported that Trump was now considering fresh sanctions against Russia as early as this week, while stressing that he could still change his mind.

He told reporters on Sunday he was ?absolutely? considering increasing sanctions on Moscow.

His predecessor Joe Biden imposed sweeping sanctions after Russia?s February 2022 invasion of Ukraine, but Trump has so far avoided what he says could be ?devastating? sanctions on Russian banks.

Trump?s recent rebukes mark a major change from his previous attitude towards Putin, whom he often speaks of with admiration and has previously held off criticizing.

The Republican tycoon promised during the 2024 election campaign to end the Ukraine war within 24 hours and said his friendship with Putin from his first term would help seal a deal.

Trump has however expressed increasing frustration with Moscow?s position in deadlocked truce negotiations with Kyiv.

?Game over?

That frustration boiled over at the weekend when Russia launched a record drone barrage at Ukraine, killing at least 13 people.

?I?ve always had a very good relationship with Vladimir Putin of Russia, but something has happened to him. He has gone absolutely CRAZY!? Trump said in a Truth Social post on Sunday night.

Trump however also criticized Ukraine?s President Volodymyr Zelensky ? with whom he had a stunning Oval Office row in February ? saying on Sunday that he was ?doing his Country no favors by talking the way he does."

Russia?s attacks have continued despite a phone call between Trump and Putin eight days ago in which the US leader said the Russian president had agreed to ?immediately? start ceasefire talks.

Moscow on Tuesday accused Kyiv of trying to ?disrupt? peace efforts and said its aerial assaults on Ukraine in recent days were a ?response? to escalating Ukrainian drone strikes on its own civilians.

US lawmakers have also stepped up calls for sanctions.

Veteran Republican Senator Chuck Grassley said on X that it was ?time for sanctions? that were strong enough for Putin to know it was ?game over.?

Two other senators, Republican Lindsay Graham and Democrat Richard Blumenthal, also called for heavy ?secondary? sanctions on countries that buy Russian oil, gas and raw materials.

Trump?s Ukraine envoy Keith Kellogg meanwhile told Fox News Tuesday that the US president?s ?frustration is understandable? after the recent Russian attacks.

Kellogg added that he expected the next peace talks between Russia and Ukraine, if they happen, to take place in Geneva after Moscow rejected the Vatican as a venue.

After that the aim would be to ?get the President, President Putin and President Zelensky together and hammer this thing out,? he added. (AFP)

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