Ukraine's President Volodymyr Zelensky has received the draft of a new US-backed plan to end Russia's war in his country, according to his office.
It also said that he is expected to hold talks with US President Donald Trump in the coming days.
Washington is understood to have signalled to Mr Zelensky that Ukraine must accept the framework to end the nearly-four-year-old war, which includes territorial concessions and curbs on its armed forces.
European countries pushed back against the plan, which sources said would require Kyiv to give up more land and partially disarm, conditions long seen by its allies as tantamount to capitulation.
"We are ready now, as before, to work constructively with the American side, as well as with our partners in Europe and around the world, so that the outcome is peace," Mr Zelensky's office said in a statement.
It added that the president's talks with Mr Trump would include discussion of the "key points required to achieve peace".
The two leaders clashed in front of television cameras during a disastrous meeting at the White House in March, but talks went more smoothly when Mr Zelensky visited Washington this summer.
Video shows Russian soldiers in Pokrovsk
The acceleration in US diplomacy comes at an awkward time for Ukraine, with its troops on the back foot on the battlefield and President Zelensky's government undermined by a corruption scandal, resulting in the firing of two cabinet ministers by parliament.
Russia played down any new US initiative to end the war.
"Consultations are not currently under way. There are contacts, of course, but there is no process that could be called consultations," Kremlin spokesman Dmitry Peskov said.
Russia had nothing to add beyond the position that President Vladimir Putin laid out at a summit with President Trump in August, Mr Peskov said, adding that any peace deal must address the "root causes of the conflict", a phrase Moscow has long used to refer to its demands.
With another winter approaching in the war, Russian troops occupy almost one-fifth of Ukraine and are poised to capture their first substantial city in nearly two years - the ruined eastern railway hub of Pokrovsk.
Video footage released by Russia's defence ministry showed its troops moving freely through its southern area, patrolling deserted streets lined with charred apartment blocks.
'Peace cannot be capitulation' - France
European Union foreign ministers - meeting in Brussels - did not comment in detail about the US plan, which has not been made public, but indicated they would not accept demands for Ukraine to make punishing concessions.
"Ukrainians want peace - a just peace that respects everyone's sovereignty, a durable peace that can't be called into question by future aggression," said French Foreign Minister Jean-Noel Barrot.
"But peace cannot be a capitulation."
German Foreign Minister Johann Wadephul said that US special envoy Steve Witkoff had - during a phone call - underlined "the importance of close coordination with Germany and our European partners" to end the war.
EU foreign policy representative Kaja Kallas said that any agreement must have the Europeans and Ukraine itself on board.
Polish Foreign Minister Radoslaw Sikorski said that Ukraine, as the victim in the conflict, should not have restrictions imposed on its ability to defend itself.
Minister for Foreign Affairs Helen McEntee said there can be no peace agreement imposed on Kyiv without its support and that of the EU.
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Washington has not commented on the reported proposals.
Secretary of State Marco Rubio said on social media that the US would "continue to develop a list of potential ideas for ending this war based on input from both sides of this conflict".
"Achieving a durable peace will require both sides to agree to difficult but necessary concessions," he added.
A US delegation, led by Army Secretary Dan Driscoll and Chief of Staff Randy George, is in Kyiv and expected to meet President Zelensky.
They held talks with Ukraine's top military commander Oleksandr Syrskyi yesterday.
He said the best way to secure a just peace was to defend Ukraine's airspace, extend its ability to strike deep into Russia and stabilise the front line.
