President Donald Trump on Tuesday signaled that his patience with Vladimir Putin is running thin, warning the Russian leader that he is “playing with fire” by refusing to engage in serious peace talks about ending the war in Ukraine.

But Trump, frustrated that Putin has shrugged at his offer to reset relations with the U.S. following a peace settlement, still hasn’t decided to shift gears.

“Putin is getting dangerously close to burning the golden bridge that Trump has set out before him,” said an administration official, who, like others, was granted anonymity to share details about the president’s current thinking.

Trump has yet to make a decision on whether to impose additional sanctions on Moscow in response to Putin ramping up attacks on Ukraine, according to four U.S. officials.

Pro-Ukraine allies on Capitol Hill are treading carefully as they urge the White House to consider following up on his threats to Putin by backing their effort to enact new sanctions. And allies in Europe, facing the possibility that Trump could walk away from peace talks without punishing Russia, are scrambling to figure out how they could tackle taking the lead on support for 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,” Trump wrote in a Truth Social post on Tuesday. “He’s playing with fire!”

Trump also told reporters on Sunday that he was “absolutely” considering additional economic sanctions on Russia and described Putin as having “gone absolutely CRAZY” in a social media post.

The president has issued similar, yet sporadic, threats since his first days in office. But at no point has he followed through and ratcheted up pressure on Moscow — despite Putin repeatedly telling Trump he supports peace while intensifying his bombing campaign in Ukraine.

“I am now very, very skeptical that Trump will ever apply any serious sanctions or measures on Russia,” said Kurt Volker, who served as Trump’s special envoy to Ukraine during his first term. “He has had so many opportunities to do it and he has always ducked.”

And many of Trump’s broadsides criticizing Putin have been diluted with strong words for other parties. Trump wrote on Sunday that Ukrainian President Volodymyr Zelenskyy and former President Joe Biden share some of the blame for the war that Putin initiated, now in its fourth year.

“This war is Joe Biden’s fault, and President Trump has been clear he wants to see a negotiated peace deal,” press secretary Karoline Leavitt said in a statement to POLITICO. “President Trump has also smartly kept all options on the table.”

Fred Fleitz, a vice chair at the America First Policy Institute who is close to the administration, praised Trump for “do[ing] his best to solve it,” but asserted that “if for some reason they can’t solve it, that failure is Biden’s.”

Fleitz said Trump’s patience with Putin is running thin. “The time is coming within the next month or six weeks where Trump may end negotiations and put in place tough sanctions,” he said.

When Trump spoke with several European leaders last week following his phone calls with both Zelenskyy and Putin, he seemed to be making excuses for Putin’s reluctance to engage in peace talks, according to two people familiar with the call. Trump, the people said, hypothesized that Putin may have balked at joining ceasefire talks after the threats of new economic sanctions by Europe and the U.S.

As frustrated as Trump has gotten with Putin, the people said, he’s given Europeans a clear sense that he doesn’t like sanctions and had hoped he could get the Russian leader to engage without forcing his hand. European leaders hope that Trump is coming to understand that the light touch with the Kremlin isn’t going to work and adjust, they said.

There are also some people inside and outside the administration who have told Trump that “sanctions will hurt U.S. companies and drive Russia away from talks,” a U.S. official said.

Several Republican lawmakers are now encouraging Trump’s sanction threats.

Senate Republican leadership backs a bipartisan sanctions bill but has been looking for a formal green light from Trump that he would support the legislation. Without his blessing, Republicans worry that it could be dead on arrival in the House, where leadership is wary of getting sideways with the president. And if he were to formally come out against more sanctions, it could bleed support for the bill or force Republicans to formally break with Trump.

Majority Leader John Thune has said the sanctions bill would easily pass the Senate, and that he would support putting it on the floor. But he’s also been careful not to get ahead of the administration. If Russia doesn’t “engage in serious diplomacy, the Senate will work with the administration to consider additional sanctions,” he said last week.

Sen. John Barrasso (R-Wyo.), the No. 2 Senate Republican, added in a Tuesday post on X that “if Russia stalls, the Senate will act decisively to move to bring lasting peace.”

But Thune is also facing pent-up desire from within his own conference to take up sanctions legislation even if Trump doesn’t offer his clear blessing. GOP senators discussed the sanctions legislation during a closed-door lunch last week, according to two attendees, who were granted anonymity to disclose private discussions.

Sen. Kevin Cramer (R-N.D.) said on Tuesday that he could see Thune bringing the bill to the floor without Trump’s blessing, although said the leader would prefer a signal from the White House.

“We want to be part of the solution and give leverage to the president, but it’s not like he doesn’t know what we’re up to,” Cramer said.

Republicans have largely left pressing Trump for more Russia sanctions to Sen. Lindsey Graham. The South Carolina Republican noted in a letter to the Wall Street Journal on Tuesday that he’s worked closely with the administration to calibrate his sanctions bill.

Graham also recently traveled with Secretary of State Marco Rubio and said he used the trip to talk up the sanctions bill and tell foreign allies that the Senate is “an independent body and that we are moving down the road to holding Putin accountable.”

European officials and longtime Russia watchers note that Moscow has sought to try and separate the war in Ukraine from the broader U.S.-Russia relationship, where both Putin and Trump see significant potential for economic rapprochement.

“It seems to us that the Russians would like to separate two topics,” said a European official.“One is Russia-U.S.-relations. And then Ukraine, as a separate topic.”

U.S. and Russian officials have both hinted at the lucrative opportunities that could follow if the two countries were to normalize bilateral relations in the wake of peace talks.

“Russia wants to do largescale TRADE with the United States when this catastrophic “bloodbath” is over, and I agree,” Trump posted on social media following his most recent call with Putin.