Pro-Russians want to secede from Ukraine

Ukraine is facing a fresh secession crisis with pro-Russians occupying the Donetsk government seat proclaiming independence and vowing to hold a referendum on joining Kremlin rule.

The declaration and subsequent appeal for Russian military help should Kiev's new pro-Western leaders resist their independence drive puts the nation of 46 million in danger of disintegration and adds still more pressure on Western powers to act.

The ex-Soviet nation on the EU's eastern frontier continues to be watched by tens of thousands of Russian troops who have already annexed the Black Sea peninsula of Crimea in response to last month's ouster in Kiev of a Moscow-backed regime.

Several heavily Russified eastern regions now want referendums on joining Russia when Ukraine holds snap presidential polls on May 25 that feature two front runners who both want to tie the country's future to Europe and break its dependence on its eastern neighbour.

The political pressure on Kiev's embattled leaders reached boiling point on Sunday when thousands chanting "Russia!" seized administration buildings in Kharkiv and Donetsk as well as the security service headquarters in the eastern region of Lugansk.

The Donetsk activists went one step further on Monday, proclaiming the creation of a sovereign "people's republic" in the region of about five million people.

Footage posted on YouTube showed one bearded Russian speaker telling the packed assembly from a podium: "Seeking to create a popular, legitimate, sovereign state, I proclaim the creation of the sovereign state of the People's Republic of Donetsk."

The industrial eastern region's Ostrov (Island) news website reported that the activists later resolved to join the Russian Federation in a move similar to the one taken by Ukraine's Crimea peninsula last month.

The Interfax news agency reported that the self-proclaimed leaders had also vowed to hold a regional sovereignty referendum no later than May 11.

More footage aired on Ukraine's Channel 5 television showed an unidentified speaker asking Moscow to send a "peacekeeping contingent of the Russian army" to Donetsk to help the region stand up to Kiev's rule.

Ukraine's latest bout of political turmoil prompted Prime Minister Arseniy Yatsenyuk to send his deputy Vitaliy Yarema to the region in order to establish a semblance of control.

The Donetsk administration building on Monday was surrounded by about 2000 Russian supporters - some of them armed.

Pro-Russian protesters also remained in control of the headquarters of the security service of the eastern region of Lugansk. Activists freed the administration building in Kharkiv on Monday after occupying it overnight.

Moscow is now lobbying for Ukraine to be transformed into a federation allowing eastern regions to adopt Russian as a second language and overrule some decisions coming from Kiev.

But Washington and the EU fear Russia, having annexed Crimea, is using the idea as an excuse to further splinter Ukraine by granting the Kremlin veto powers over Kiev's regional policies.