Ukrainian President Volodymyr Zelensky has warned that Kyiv risks losing US support over a White House plan on how to end the war with Russia.

Addressing the nation on Friday, Zelensky said Ukraine “might face a very difficult choice: either losing dignity, or risk losing a key partner”, adding that “today is one of the most difficult moments in our history”.

The widely leaked US peace plan includes proposals that Kyiv had previously ruled out: ceding eastern areas it now controls, significantly cutting its army size, and pledging not to join Nato.

These provisions are seen as heavily slanted towards Russia, whose President Vladimir Putin said the plan could be a “basis” for peace settlement.

At Friday’s meeting with his security cabinet, Putin said Moscow had received the plan, which had not been discussed with the Kremlin in detail. He said Russia was willing to “show flexibility” but was also prepared to fight on.

Later in the day, US President Donald Trump said Zelensky would “have to like” the plan, adding that otherwise Ukraine and Russia would continue fighting.

Ukraine is critically dependent on deliveries of US-made advanced weaponry, including air defence systems to repel deadly Russian air assaults, as well as intelligence provided by Washington.

Russia launched a full-scale invasion of Ukraine in 2022.

In his 10-minute address in front of the presidential office in Kyiv, Zelensky warned that Ukraine would face “a lot of pressure… to weaken us, to make divide us”, adding that “the enemy is not sleeping”.

Urging Ukrainians to stay united, he stressed that the country’s “national interest must be taken into account”.

“We’re not making loud statements,” he went on, “we’ll be calmly working with America and all the partners… offering alternatives” to the proposed peace plan.

Zelensky also said he had been reassured of continuous support during a phone call with UK Prime Minister Sir Keir Starmer, French President Emmanuel Macron and German Chancellor Friedrich Merz.

After the talks, Starmer stressed that “the principle that Ukraine must determine its future under its sovereignty is a fundamental principle”.

Separately, Zelensky said he had spoken “for almost an hour” with US Vice-President JD Vance and Army Secretary Dan Driscoll, adding that Ukraine “always respected” President Donald Trump’s efforts to end the war.

In Washington, Trump warned that Ukraine would lose more territory to Russia “in a short amount of time”.

He said it was “appropriate” to give Ukraine until 27 November – Thanksgiving in the US – to agree to the peace deal, but added deadlines could be extended if things were “going well”.

Speaking at the White House later on Friday, the US president said “we think we have a way of getting peace”, adding that Zelensky “is going to have to approve it”.

Washington has been pressing Kyiv to quickly accept the plan, and sent senior Pentagon officials to the Ukrainian capital earlier this week.

On Thursday, President Putin sounded determined to continue the war despite reported heavy Russian combat casualties.

“We have our tasks, our goals,” the Kremlin leader, wearing a military uniform, told his army commanders. “The chief one is the unconditional achievement of the aims of the special military operation [full-scale war].”

The 28-point US peace plan emerged as Russia claims small territorial gains in south-eastern Ukraine, while Zelensky faces a domestic crisis implicating top officials in a $100m (£76m) corruption scandal.

The White House has pushed back on claims that Ukraine was frozen out of the drafting of the proposal, following meetings between US special envoy Steve Witkoff and Russian counterpart Kirill Dmitriev.

An unnamed US official told CBS News, the BBC’s US partner, that the plan was drawn up “immediately” following discussions with Ukraine’s top security official Rustem Umerov, who agreed to the majority of it.

Umerov is said to have made several modifications before he presented it to Zelensky.

The leaked draft proposes Ukrainian troops’ withdrawal from the part of the eastern Donetsk region that they currently control, and de facto Russian control of Donetsk, as well as the neighbouring Luhansk region and the southern Crimea peninsula annexed by Russia in 2014.

The plan also includes freezing the borders of Ukraine’s southern Kherson and Zaporizhzhia regions along the current battle lines. Both regions are partially occupied by Russia.

The US plan also limits Ukraine’s military to 600,000 personnel, with European fighter jets stationed in neighbouring Poland.

Kyiv would receive “reliable security guarantees”, the plan says, although no details have been given. The document says “it is expected” that Russia will not invade its neighbours and that Nato will not expand further.

The draft also suggests Russia will be “reintegrated into the global economy”, through the lifting of sanctions and by inviting Russia to rejoin the G7 group of the world’s most powerful countries – making it the G8 again.

Ukrainians both under and free of Russian occupation struck a defiant tone in reaction to news of the US proposal.

In Kyiv, the widow of a Ukrainian soldier told the BBC: “This is not a peace plan, it is a plan to continue the war.”

Another person speaking from one of the occupied territories in Ukraine told the BBC: “I’m trying to keep my sanity here in the conditions of constant propaganda that Ukraine has forgotten us. I hope they will not sign this.”

Russia currently controls about 20% of Ukrainian territory and its troops have been making slow advances along the vast front line, despite reported heavy losses.