Edge's News: Ukraine Ask British nationals to leave immediately amid concerns an of invasion..

The Foreign Office updated its advice on Friday evening to tell UK nationals to ‘leave now while commercial means are still available’.

The dire warning came after Boris Johnson voiced fears for the security of Europe during a call with world leaders including US President Joe Biden.

Defence Secretary Ben Wallace said an invasion could come ‘at any time’, with Russian President Vladimir Putin having amassed an estimated 130,000 troops on the border with Ukraine.

Mr Biden’s national security adviser Jake Sullivan described the possibility of an incursion of some sort taking place before the end of the Winter Olympics on February 20 as being a ‘credible prospect’ and a ‘very, very distinct possibility’.

He said new Russian forces were arriving at the border and they are in a position to ‘mount a major military operation in Ukraine any day now’, which could include a ‘rapid assault on the city of Kyiv’ or on other parts of the country.

Speaking from the White House, Mr Sullivan said Russia could choose ‘in very short order to commence a major military action against Ukraine’, but stressed the US does not know whether Mr Putin has made a final decision.

Mr Sullivan said the ‘threat is now immediate enough’ to urge Americans to leave Ukraine ‘as soon as possible and in any event in the next 24 to 48 hours’.

Warning US citizens to leave the country immediately, he continued: ‘If you stay, you are assuming risk with no guarantee that there will be any other opportunity to leave and no prospect of a US military evacuation in the event of a Russian evasion.

‘If a Russian attack on Ukraine proceeds, it is likely to begin with aerial bombing and missile attacks that could obviously kill civilians without regard to their nationality.

‘A subsequent ground invasion would involve the onslaught of a massive force.

‘With virtually no notice, communications to arrange a departure could be severed and commercial transit halted.’

In a call lasting around 80 minutes, Downing Street said Mr Johnson urged Nato allies to make it clear to Moscow there is a ‘heavy package of economic sanctions ready to go’.

‘The Prime Minister told the group that he feared for the security of Europe in the current circumstances,’ a No 10 spokeswoman said, in an account of the call that included French President Emmanuel Macron, German Chancellor Olaf Scholz and Nato secretary-general Jens Stoltenberg, as well as EU leaders Ursula von der Leyen and Charles Michel.

Mr Johnson warned that the penalties would be ‘extremely damaging’ to Russia’s economy and urged that allies must reinforce Nato’s eastern frontiers.

The Foreign Office followed the US in advising against all travel to Ukraine, with a spokesman saying: ‘The safety and security of British nationals is our top priority, which is why we have updated our travel advice.

‘We urge British nationals in Ukraine to leave now via commercial means while they remain available.’

Earlier in the day, Mr Wallace held talks in Moscow with Russian defence minister Sergei Shoigu as part of diplomatic efforts to avert war.

He told a news conference in the British Embassy: ‘Currently there’s over 130,000 troops stationed at readiness or exercising – plus warplanes, plus ships into the Black Sea – on the borders of Ukraine and that is an action that is not normal.

‘It is beyond normal exercising therefore we will judge that statement on the evidence.’

Following a frosty meeting in Moscow on Thursday between Foreign Secretary Liz Truss and her counterpart Sergei Lavrov, Mr Wallace said his discussions with Mr Shoigui had been ‘frank and constructive’.

While he said that he took the minister’s assurances ‘seriously’, he admitted he was less optimistic than he had been previously that there could be a diplomatic solution to the crisis.

He said the current disposition of Russian forces meant they could do ‘a whole range of actions, including an invasion of a neighbouring country, at any time’.