President Trump stated Friday that the U.S. would abandon peace efforts regarding Ukraine if Russian President Vladimir Putin rejects ceasefire terms.

“If one party is being difficult, we will call them foolish and horrible and simply move on,” Trump told reporters. “Hopefully, we won’t have to do that.”

Trump’s remarks mirrored those of Secretary of State Marco Rubio, who spoke earlier Friday in Paris after a meeting with special envoy Steve Witkoff, French President Emmanuel Macron, and officials from Ukraine, Germany, and the U.K. This meeting, the first of its kind, suggested increased European participation in U.S. attempts to secure a deal.

While Ukraine has reportedly agreed to both complete and temporary ceasefire proposals, any agreement has been delayed for weeks, though Russia is largely thought to be maintaining a 30-day ceasefire regarding Ukraine’s energy infrastructure.

“If the differences are too great, the president is prepared to proceed without further negotiation,” Rubio told reporters in Paris, describing the talks as “very positive.”

“We will not continue endless meetings if progress isn’t being made,” Rubio said. “We will shift our focus to other issues that are equally, if not more, important to the U.S.”

It is unclear what the U.S. position would be regarding aid to Ukraine if Russia refuses to end its invasion, and whether Trump would follow through on previous threats of additional sanctions against Russia.

Last month, Trump told NBC News that he was “very angry” after Putin initially signaled interest in a ceasefire with Ukrainian President Volodymyr Zelenskyy.

“If Russia and I cannot reach an agreement to stop the bloodshed in Ukraine, and if I believe it is Russia’s fault — and it might not be — I will impose secondary tariffs on all oil coming out of Russia,” he said.

“If you buy oil from Russia, you cannot do business in the United States,” he added. “There will be a 25% to 50% tariff on all oil.”

Trump declined to specify how long Russia has to demonstrate its commitment to ending the war, but he told reporters Friday that it needs to happen “quickly — we want to get it done.”