Russia approves troop deployment in Ukraine

He had asked that Russian forces be used "until the normalisation of the political situation in the country".

Russia's Black Sea Fleet is based in the Ukrainian region of Crimea, where many ethnic Russians live.

Kiev has reacted angrily to days of military movements in Crimea, accusing Moscow of trying to provoke the new government into an armed conflict.

Interim President Olexander Turchynov has called an emergency session of his security chiefs.

Meanwhile, big pro-Russian rallies have been held in several Ukrainian cities outside Crimea:

In Donetsk, Mr Yanukovych's traditional stronghold, demonstrators from a crowd of some 7,000 tried unsuccessfully to occupy the regional administration building, raising a Russian tricolour on a nearby flag-post

In Kharkiv, Ukraine's second-biggest city, dozens of people were injured after scuffles between pro- and anti-Russian protesters broke out outside the regional administration building

In Mariupol, in the south-east, hundreds of protesters carrying Russian flags gathered outside the city council in eastern and southern Ukraine.