Some embassy staff and dependents are being withdrawn from Ukraine, but the embassy remains open and will continue to carry out essential work, it said.

"The FCDO advise against all travel to Donetsk oblast, Luhansk oblast and Crimea. The FCDO advises against all but essential travel to the rest of Ukraine," it said.

Britain's move came after the US Department of State on Sunday ordered eligible family members of staff at its embassy in Ukraine to leave the country.

Ukraine's Ministry of Foreign Affairs said it considered the US decision "premature and a manifestation of excessive caution."

Meanwhile, Josep Borrell, high representative of the European Union for Foreign Affairs and Security Policy, told reporters on Monday "we are not going to do the same thing because we don't know any specific reasons."