Volodymyr Zelenskyy has said Ukraine is "ready to come to the negotiating table as soon as possible" in the search for a "lasting" peace with Russia.
The Ukrainian president made the statement on social media hours after Donald Trump's White House announced it was pausing US military aid to Kyiv.
He also said he was "ready to sign" a deal giving the US access to minerals in Ukraine - which has been a sticking point between the countries in the last week, with Kyiv seeking security guarantees in return.
It comes after vice president JD Vance said a potential European peacekeeping force in Ukraine would be "20,000 troops from some random country that hasn't fought a war in 30 or 40 years" - sparking anger from a number of UK politicians.
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The Ukrainian president stopped short of saying sorry in the statement, but outlined how the first stages of a possible peace deal might work.
He also reiterated how grateful he was for American support for Ukraine, after Mr Vance criticised him, claiming he had not shown enough gratitude during his explosive White House visit.
Mr Zelenskyy added: "Our meeting in Washington, at the White House on Friday, did not go the way it was supposed to be.
"It is regrettable that it happened this way. It is time to make things right.
"We would like future cooperation and communication to be constructive."
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Earlier, a White House official, speaking anonymously, said: "President [Trump] has been clear that he is focused on peace.
"We need our partners to be committed to that goal as well. We are pausing and reviewing our aid to ensure that it is contributing to a solution."
There was no indication about the possible length of the pause, and there's been no comment so far from Ukraine.
It comes after the astonishing clash between the two leaders - as well as Mr Vance - in the Oval Office on Friday.
Mr Trump's berating of Mr Zelenskyy was condemned by many and has led to a show of support from European leaders as they try to formulate their own way forward.
The US president attacked the Ukrainian leader again on Monday, telling reporters he should be "more appreciative".
Writing on Truth Social, Mr Trump also said Mr Zelenskyy had made "the worst statement that could have been made" after he commented that peace was still "very, very far away".
"America will not put up with it for much longer!" he posted.
"It is what I was saying, this guy doesn't want there to be peace as long as he has America's backing," the president added.
Mr Zelenskyy then posted on X that Ukraine was "working together with America and our European partners and very much hope on US support on the path to peace".
"Peace is needed as soon as possible," he said.
Despite the diplomatic crisis, Mr Trump has said a deal is still possible.
An agreement giving the US access to Ukraine's rare earth metals was meant to have been signed by the two presidents on Friday.
It was billed as an important step in a future peace deal - and part payback for aid already received.
However, the dramatic falling out has thrown that into jeopardy.
Mr Zelenskyy wants the metals deal to include guarantees on halting Russia should it break the terms of any peace agreement.
Zelenskyy showed 'lack of respect'
Mr Vance suggested on Monday that the metals pact was the best way to secure a lasting end to the war.
"If you want real security guarantees, if you want to actually ensure that Vladimir Putin does not invade Ukraine again, the very best security guarantee is to give Americans economic upside in the future of Ukraine," Mr Vance told Fox News.
"That is a way better security guarantee than 20,000 troops from some random country that hasn't fought a war in 30 or 40 years," he added.
Mr Vance said Mr Zelenskyy had shown a "lack of respect" and "a certain sense of entitlement" in Friday's trip to Washington.
He repeated that the door was still open if he altered his approach, but told Fox News he "still isn't there".
European and world leaders - who met Mr Zelenskyy at the weekend - have discussed a potential "coalition of the willing" to deploy peacekeepers and deter further Russian aggression.
UK Prime Minister Sir Keir Starmer said Britain was prepared to put "boots on the ground and planes in the air" under the plan - but it's unclear who else might participate.
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He told MPs on Monday that Britain must "lead from the front" on supporting Ukraine and the "security of our continent, the security of our country".
However, the prime minister believes any international deployment of troops must have a US "backstop" deterrent to be taken seriously by Russia.
America has given around €64bn (£53bn) of military aid to Ukraine, compared with €62bn (£51.3bn) from European nations (including Britain).
The overall US total is €114bn (£94bn) and the European one €132bn (£109bn). This includes humanitarian aid and other financial assistance to keep the country running.
Following the weekend summit, the UK also pledged £1.6bn in finance for Ukraine to buy another 5,000 air defence missiles.
(c) Sky News 2025: Zelenskyy says Ukraine 'ready to come to negotiating table' - after US pauses military aid