U.S. President Donald Trump on Friday renewed his threat to impose sanctions on Russia unless progress is made to reach a peace deal with Ukraine, as tensions between Moscow and Washington escalated.

Trump appeared to set a two-week deadline for Russian President Vladimir Putin to show more willingness to end his invasion of Ukraine. So far, Moscow hasn’t offered any concessions for a truce deal and has demanded more territorial concessions from Kyiv. 

Speaking to reporters at the White House on Friday, Trump said he would “make a decision as to what we do, and it’s going to be a very important decision, and that’s whether or not it’s massive sanctions or massive tariffs or both, or do we do nothing and say it’s your fight?”

Ukrainian President Volodymyr Zelenskyy earlier Friday accused Moscow of dragging out peace talks in a bid to hold off American sanctions, which Trump has threatened to impose on Russia and its trading partners if the Kremlin does not show more efforts toward ceasefire negotiations.

A Russian airstrike on Thursday hit a U.S. electronics factory operating in western Ukraine, injuring at least 15 people, according to Ukrainian officials. Asked about the strike, Trump told reporters “I’m not happy about it, and I’m not happy about anything having to do with that war.”

“Over the next two weeks, we’re going to find out which way it’s going to go. And I better be very happy,” Trump said.

The U.S. president has made considerable diplomatic efforts to end the war in Ukraine in the last two weeks, but has so far failed to get Moscow to make any concessions. Russia still wants Ukraine to give up vast swathes of territory in its eastern Donbas region, a request that Kyiv categorically rejects.

Earlier this month, Trump met with Putin in Alaska in a bid to convince the Russian ruler to end his full-scale invasion of Ukraine. The U.S. president then convened European leaders in the White House last Monday, including Zelenskyy, to discuss the prospects for a peace deal.

Shortly after, Trump announced that a bilateral meeting between Putin and Zelenskyy was in the works. But Russian Foreign Minister Sergey Lavrov said on Friday that no Putin-Zelenskyy summit is planned, saying the agenda for such a meeting “is not ready at all.”

Finnish President Alexander Stubb, who attended the talks in the Oval Office, said Washington’s patience with Moscow seemed to be “wearing thin,” in an interview with Finnish TV outlet YLE TV1 on Saturday.