Crimea's parliament voted to join Russia yesterday and its Moscow-backed government said it would hold a referendum on the decision within 10 days, in an escalation of the crisis over the Ukrainian Black Sea peninsula.
The acceleration of moves to bring Crimea, which has effectively been seized by Russian forces, formally under Moscow's rule came as European Union leaders gathered for a summit to seek ways to pressure Russia to back down.
The Crimean parliament voted unanimously "to enter into the Russian Federation with the rights of a subject of the Russian Federation".
The vice-premier of Crimea, home to Russia's Black Sea military base in Sevastopol, said the referendum would take place on March 16. He said all state property would be "nationalised" and that the Russian rouble could be adopted as Crimea's currency.
The announcement, which diplomats said could not have been made without Russian President Vladimir Putin's approval, raised the stakes in the most serious east-west confrontation since the cold war.
Far from seeking a diplomatic way out, Putin appears to have chosen to create facts on the ground before the West can take more than token action against him.
Ukraine's interim government has declared the referendum illegal and opened a criminal investigation against Crimean Prime Minister Sergei Askyonov, who was appointed by the region's parliament last week. The Ukrainian government does not recognise his authority or that of the parliament.
The European Union on Thursday suspended talks with Russia on a wide-ranging economic pact, and on a visa deal to grant Russian citizens visa-free travel within the 28-nation bloc, punishing Moscow for its military incursion into the Crimea.
The move in Brussels came on the heels of sanctions by the Obama administration in Washington, which ordered the freezing of US assets and a ban on travel to the US of those involved in the Russian intervention in Crimea.
On Crimea's regional border with the rest of Ukraine, gunmen stopped a group of 40 unarmed military observers from the Organisation for Security and Co-operation in Europe carrying out an inspection mission requested by Ukraine's government.
Wider diplomatic efforts to defuse the crisis also appeared to stall, with a second round of talks between US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov in two days ending with no agreement.
Additional reporting by Agence France-Presse and Associated Press