RUSSIA has lashed out at a proposal to send 30,000 Nato troops to Ukraine in a potential peacekeeping missing.
Sir has said he is "ready and willing" to put British boots on the ground in the war-torn country.
It would come as part of a security guarantee in the event of some sort of a ceasefire deal between Moscow and Kyiv.
Sir Keir is planning to present a plan to Donald Trump to send 30,000 European troops to Ukraine to police a 1000km frontline.
He is expected to ask for American jets and weapons to be on standby in Eastern Europe under the plan, the reported.
But Vladimir Putin's puppet spokesman has branded the proposal as "unacceptable" because it would involve forces from a Nato member state and therefore have ramifications for Russia's own security.
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Dmitry Peskov said: "This causes concern for us, because we're talking about sending military contingents - about the possible, eventual sending of military contingents from Nato countries to Ukraine.
"This takes on a completely different meaning from the point of view of our security. We're monitoring this very closely."
It comes as Volodymyr Zelensky is set to meet a US special envoy Keith Kellogg after being called a "dictator" by Trump.
Kellogg has already today met with Ukrainian foreign minister Andrii Sybiha to discuss ways to achieve a "just and lasting peace".
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Sybiha said: "I affirmed Ukraine's willingness to achieve peace through strength and our vision for the necessary steps."
He reiterated to Kellogg, who arrived in the Ukrainian capital on Wednesday and said he would "sit and listen" as part of his mission, that the security of Ukraine and the transatlantic "is indivisible".
Kellogg's visit to Ukraine comes amid a period of diplomatic turmoil between the two countries after Trump lashed out at Zelensky.
The sparked uproar yesterday after lashing out at Ukraine's wartime leader and accusing him of "refusing to have elections".
In a shocking social media rant, Trump warned “modestly successful comedian” Zelensky must “move fast or he is not going to have a country left”.
Trump also claimed the Ukrainian president talked the US into "spending $350 billion dollars to go into a war that couldn't be won".
He also later insisted he "trusts" that Russia wants peace after branding Zelensky a "dictator without elections".
Trump then once again labelled Zelensky a "dictator" after the Ukrainian leader said he was "living in a disinformation space".
He told : "I think the Russians want to see the war end, I really do.
"I think they have the cards a little bit, because they've taken a lot of territory. They have the cards."
The White House has continued to press Kyiv today - urging Ukraine to rein in criticism.
Mike Waltz, the White House national security adviser, told Fox News: "They need to tone it down and take a hard look and sign that deal."
Wrong, Donald
The Sun Says...
DONALD Trump’s smearing of the Ukraine regime as scam artists who provoked a war using US taxpayers’ money is a rant beneath the dignity of his office.
Almost nothing in it is true.
It reads like a post on a forum for conspiracy theorists. It is an unprecedentedly shocking statement from the President of the United States.
Vladimir Putin has made no secret of his imperialist ambitions, nor his denial of his neighbour’s right to exist as a sovereign, free country.
He invaded Ukraine, butchered and raped its people, stole its children and bombed its cities.
President Zelensky — far from duping anyone or inviting the conflict, far from being a “dictator without elections” — has been a heroic wartime leader who needs Western aid to overcome staggering odds.
The idea he is riding a “gravy train” is laughable. And his people, with whom he remains highly popular whatever Trump claims, have resisted conquest with immense bravery.
It is troubling and short-sighted in the extreme for the so-called leader of the free world to have no interest in a war raging in Europe because he is separated from it by the Atlantic.
America is not a business where Trump, as CEO, has no task except to slash costs and maximise profits. It is the most powerful democracy on Earth with global responsibilities and — let’s be frank — a duty to discern right from wrong with absolute moral clarity.
Others in the White House should urgently point this out.
But even Zelensky's rivals in Ukraine are supporting him - and have hit back at Trump's suggestion the embattled nation should hold elections.
Ukraine has been under martial law since Putin ordered an illegal invasion in February 2022.
A presidential election was due to take place last spring, but was postponed as Moscow presses on with its war.
Trump also falsely claimed Zelensky has just a four per cent approval rating, which was roundly dismissed.
Rivals of Zelensky in Ukraine have rebutted Trump's declaration that an election should be held.
Former prime minister Yulia Tymoshenko, the leader of the oppositional Motherland faction, insisted elections are "impossible" in wartime.
She said: "Only Ukrainians have the right to decide when and under what conditions they should change their power.
"There are no such conditions today!
"Elections during a war are impossible and immoral, because our military will not be able to participate in them.
"And without them, elections will never be legitimate.
"Voting during the war will also not be called honest, because the people will not be able to control it."
Ukrainian MP Lesia Vasylenko, of opposition party Holos, also backed not holding an election.
She told : "I'm an opposition MP, and still we are all speaking up in one voice saying that what America today proposed for Ukraine is absolutely unacceptable.
"We are living in martial law because Russia has attacked Ukraine in 2014 then escalated that very aggression to an all-out war.
"So we in Ukraine have no choice but to live in martial law to protect ourselves.
"Is President Zelensky a dictator? No. He is a president of a free democratic country which is fighting for its survival."
Trump's tirade came after he said he was disappointed Zelensky had complained about being left out of peace talks with Russia.
He said Kyiv should have been willing to make concessions and: “You should have never started it. You could have made a deal.”
Mr Zelensky responded by saying: “With all due respect to President Donald Trump, as leader of a nation we respect greatly . . . he is living in this disinformation space.”
Zelenksy said he is "counting on Ukrainian unity" as well as the "unity of Europe" and the "pragmatism of America" for victory.
He said Ukraine has wanted an end to the war from "the very first second that" Russia invaded in February 2022 and that he wants a peace deal that will ensure Moscow will not attack again.
The UK's culture secretary Lisa Nandy today backed Sir Keir's contradiction to Trump's comments calling the Ukrainian leader a "dictator".
She told BBC Radio 4's Today programme: "The Prime Minister has made his own view clear.
"He spoke to President Zelensky in the last few days and made clear that he understands, first of all that he is an elected leader, and we consider him in the United Kingdom to be a legitimate leader."
Asked whether she was saying Trump is wrong, Ms Nandy added: "We take a different view. We do not consider President Zelensky to be a dictator."
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She said that Zelensky was "elected by the people" and "Russian aggression" is the reason elections have not been held.
"We stand with Ukraine, and our belief in that our support for Ukraine is unshakeable," she added.
Why wartime elections are rare
ELECTIONS in Ukraine were suspended under martial law following the 2022 invasion.
Presidential elections were due to be held last year, but were postponed amid the ongoing war.
Zelensky's term would have ended in May 2024, but under martial law elections are suspended.
Ukraine's martial law was drafted in 2015, soon after Russia annexed Crimea.
Experts have said it would be practically impossible to hold elections in Ukraine as Russia continues to attack cities and thousands have been displaced.
Sir Keir Starmer said it was "perfectly reasonable" for Ukraine to "suspend elections during wartime as the UK did during World War Two", Downing Street said.
In October 1944, Winston Churchill extended parliament by a further year pending the final defeat of Nazi Germany.
There had not been a general election since 1935 and Churchill vowed to hold one as soon as hostilities were over.