France advises nationals against non-essential travel to Ukraine

Due to the Russian military build-up on the border with its neighbour, "it is recommended to exercise heightened vigilance", the ministry said in a statement.

"It is strongly recommended to avoid border areas in the north and the east of the country," the statement said.

"As far as possible it is recommended to postpone any travel to Ukraine that is not essential or urgent," the ministry said.

On Sunday, the US State Department issued a travel advisory warning Americans not to travel to Russia "due to ongoing tension along the border with Ukraine".

For its part, Ukraine's foreign ministry said the US move was "premature", calling it "a display of excessive caution".

The European Union said it would not follow Washington's lead, top European diplomat Josep Borrell adding that there was no need to "dramatise" the situation while talks with Russia continue.

However Britain's foreign ministry said Monday it was withdrawing some staff and their relatives from its embassy in Ukraine in response to the "growing threat from Russia".

Australia's foreign ministry has also advised citizens not to travel to Ukraine, directing dependents of Australian embassy staff in Kyiv to leave the country.

The NATO alliance said Monday it was sending jets and ships to bolster its eastern European defences, as the US and EU looked to coordinate a tough response to Russia if it invades Ukraine.