Ukraine’s interim prime minister has warned the Crimean parliament “no-one in the civilised world” will recognise its referendum on joining Russia.
Arseniy Yatsenyuk and others in the Kiev government have called the vote “unconstitutional” and “illegitimate”.
But the referendum has the support of the Russian parliament.
The speaker of the upper house said if the Crimean people vote on 16 March to join Russia then they would “unquestionably back this choice”.
The decision by Crimean MPs to seek to join the Russian Federation comes amid international tensions over the presence of pro-Russian troops in the southern Ukrainian peninsula.
The Kremlin said, after a telephone conversation between President Vladimir Putin and his US counterpart Barack Obama, that differences remained in their approach and assessment of the crisis.
Meanwhile, Ukraine’s Paralympic team has confirmed it will take part in the Sochi Winter Paralympics, which begins later.
The head of the team, Valeriy Sushkevich, said they would participate “so they remember us, remember Ukraine – a sovereign state, which sent its athletes here”.
But he said: “If something major happens, Ukraine will leave the Games immediately”.
Prime Minister Yatsenyuk said on Friday Ukraine was open to talks with Russia as long as it withdraws its troops and abides by international agreements.
In a warning to the “separatist and other traitors of the Ukrainian state”, he said: “Any decision of yours is deliberately unlawful and unconstitutional and no-one in the civilised world will recognise the decision of the so-called referendum of the so-called Crimean authorities”.