The United States is to decide within days if a ceasefire deal to end the war in Ukraine is “doable”, according to Secretary of State Marco Rubio.
He said the US will stop trying to broker a peace deal unless there are clear signs that one can be reached.
Mr Rubio said US President Donald Trump was still interested in a deal, but had many other priorities around the world and was willing to move on unless there are signs of progress.
“We’re not going to continue with this endeavour for weeks and months on end. So we need to determine very quickly now, and I’m talking about a matter of days whether or not this is doable in the next few weeks. If it is we’re in. If it’s not, then we have other priorities to focus on as well,” he said.
During the US presidential election campaign, Mr Trump said very little about Ukraine except that he would end the war in a day. However, he had given no details on how exactly he would do that.
He moderated that claim on taking office, suggesting a deal by April or May, as obstacles mounted.

Mr Rubio’s comments come after talks yesterday involving US and European officials on the three-year-old conflict.
The meetings included Mr Rubio, French President Emmanuel Macron, US envoy Steve Witkoff, British Foreign Secretary David Lammy, German officials and Ukrainian ministers.
France said the talks had launched a “positive process”, as Europe seeks to be included in efforts to end the conflict.
They took place as Mr Trump’s push to end the war stumbles, with Russia’s President Vladimir Putin rebuffing a complete truce.
“Today in Paris, we launched a positive process in which the Europeans are involved,” the French presidency said.
A new meeting of envoys from the US, France, Britain, Germany and Ukraine will take place next week in London, it added.
Mr Rubio later called Russia’s Foreign Minister Sergei Lavrov to discuss the Paris meeting.
“President Trump and the United States want this war to end, and have now presented to all parties the outlines of a durable and lasting peace,” Mr Rubio told his Russian counterpart, according to the US State Department.
“The encouraging reception in Paris to the US framework shows that peace is possible if all parties commit to reaching an agreement,” he added.
In a statement, Russia’s foreign ministry said Mr Lavrov “reaffirmed Moscow’s readiness to continue collaborative efforts with American counterparts to comprehensively address the root causes of the Ukrainian crisis”.
Mr Lavrov and Mr Rubio agreed on the need to maintain “prompt communication channels”, in light of the London meeting next week, the statement said.
‘Europeans at the table’
Ukrainian President Volodymyr Zelensky, who has clashed with Mr Trump, praised the talks, saying it was important to work towards “real security” in Europe.
Posting on Telegram, Mr Zelensky’s chief of staff Andriy Yermak thanked Mr Macron “for your efforts in the process of achieving a just and lasting peace for Ukraine”.
However Kremlin spokesman Dmitry Peskov dismissed the Paris meeting, saying earlier that Europeans seemed to have “a focus on continuing the war”.
France and Britain have sought a coordinated European response to defending Ukraine, during the conflict and in any ceasefire, after Mr Trump shocked them by opening talks with Russia.
Mr Macron said the Paris talks were “a very important occasion for convergence,” as everybody wanted “a robust and sustainable peace”.
French Foreign Minister Jean-Noel Barrot told reporters the talks had made a breakthrough because the United States, Ukraine, and European ministers had “gathered around the same table” when Europe had previously feared it would be excluded from decision-making.
The United States “has understood that a just and sustainable peace … can only be achieved with the consent and contribution of Europeans,” he added later on LCI television.