Russian President Vladimir Putin has signed a decree recognising Crimea as a sovereign state, paving the way for it to be absorbed into Russia.
The decree said it had taken into account Sunday’s referendum in Crimea, in which officials said 97% of voters backed breaking away from Ukraine.
The EU and US said the referendum was illegal and imposed sanctions on 21 officials from Russia and Ukraine.
Crimea was taken over by pro-Russian gunmen in late February.