Britain has urged its citizens to leave Ukraine as world leaders voiced heightened concerns of an invasion by Russia in the coming weeks.
The UK Foreign Office said British citizens should “leave while commercial means are available” and warned against travel to the country in an updated advisory.
It comes as new satellite images of Russian troop movements in Eastern Europe showed what Nato called a relentless military build-up that threatens Ukraine.
“The safety and security of British nationals is our top priority, which is why we have updated our travel advice,” a UK Foreign Office statement said.
“We urge British nationals in Ukraine to leave now via commercial means while they remain available.”
On Friday evening, Prime Minister Boris Johnson told world leaders, including US President Joe Biden, that he fears for the security of Europe “in the current circumstances".
He held a virtual meeting with the leaders of the US, Italy, Poland, Romania, France, Germany, the European Council, the European Commission and Nato to discuss the situation.
“He impressed the need for Nato allies to make it absolutely clear that there will be a heavy package of economic sanctions ready to go, should Russia make the devastating and destructive decision to invade Ukraine,” a Downing Street representative said.
US company Maxar Technologies, which has been tracking troop movements for months, said its pictures showed new groups of Russian troops in Crimea, Belarus and near the Ukrainian border.
These included 550 troop tents and hundreds of Russian vehicles parked at an airfield in Oktyabrskoye in annexed Crimea, Maxar said, while other equipment was seemingly moved to the coast of the peninsula.
Maxar said more troops and forces had been stationed at the Kursk training area in western Russia, about 100 kilometres from the Ukrainian border.
European diplomats are working to avoid war breaking out in Ukraine amid fears that Russia plans to invade its ex-Soviet neighbour.
UK Defence Secretary Ben Wallace said he was not as optimistic as he used to be about quelling the crisis on the Ukrainian border.
Nato Secretary General Jens Stoltenberg said on Thursday that while the number of Russian forces was going up, the warning time for a possible attack was decreasing.
Russia has stationed “well over” 100,000 troops on the Ukrainian border with heavy equipment and medical units, he said.
And he described a simultaneous Russian deployment in Belarus, an ally of Moscow, as the biggest since the break-up of the Soviet Union.
The Maxar images were said to show newly arrived helicopters, troops and military vehicles in Belarus before joint drills between Russia and its ally.
Russia has not disclosed how many troops it has sent and says it has the right to move forces around on its territory as it sees fit.
But Nato fears Russia is planning an invasion of Ukraine and that troops may not return home from Belarus after the joint exercises.
Frantic diplomacy this week by the leaders of Britain, France and Germany has raised hopes of averting war, but Russia played down a claim by French President Emmanuel Macron that it had promised not to escalate matters.
Nato countries have moved to bolster the defences of member countries on the alliance’s eastern flank, with the UK sending 350 troops to Poland and Germany posting the same number to Lithuania.
Although Nato sees these as defensive movements, Russia’s version of events is that western powers are to blame for the high tension.
