No military evacuation for Brits in Ukraine - UK govt

"There will be a big difference between what they may have seen on their TV screens in Afghanistan over the summer and what may happen over the next week or so, and that is that the Royal Air Force will not be in a position to go in and to fly people out," he said.

Highlighting the build-up of Russian troops on the Ukrainian border, Heappey urged British citizens in Ukraine to take notice and to leave immediately.

Heappey also said Britain's involvement in Ukraine will be limited to NATO's eastern borders. "We won't play an active part in Ukraine but what we absolutely will do is stand on NATO's eastern borders to reassure our allies in NATO that at a time of acute crisis on the European continent, probably the most acute moment of crisis for 70 years, that our role within NATO is steadfast and our support for our allies is unstinting," said Heappey.

On Friday (February 11) the UK government advised British nationals to leave Ukraine now while commercial means were still available and advised against all further travel to the country.