The Ukrainian Prime Minister Arseniy Yatsenyuk says his country will never recognise Russia’s annexation of Crimea – and warns that he believes Moscow has other expansionist plans.

“The biggest disaster of this century will be a resurrection of the Soviet Union – what President Putin wants, clearly. This kind of very dangerous idea is supported by the vast majority of Russian people,” he said.

Ukraine has accused Russian forces of playing a role in the violence against Maidan demonstrators that claimed more than 100 lives.

Moscow denies the charges, pointing the finger at Ukraine’s secret services under ex-President Yanukovych.

On Friday the Russian foreign minister tackled Ukraine over constitutional reforms. His concern is that the interests of the country’s Russian-speaking communities will not be taken into account.

“The main obstacle to the settling of this crisis is inside Ukraine. And this obstacle is that the current Ukrainian authorities are incapable of completely and equally respecting the rights of all Ukrainians without exception,” Sergei Lavrov told a news conference.

Another example of the stark divisions emerging came amid emotional goodbyes on Friday as 200 cadets graduated in Crimea. They have chosen not to pursue careers with the Russian navy, but to travel to Odessa to join the Ukrainian fleet to which they originally pledged loyalty when they entered college.