Russian president Vladimir Putin recognised two breakaway regions in eastern Ukraine as independent entities on Monday, upping the ante in a crisis the West fears could unleash a major war.
In a lengthy televised address, Putin described Ukraine as an integral part of Russia's history and said eastern Ukraine was ancient Russian lands and that he was confident that the Russian people would support his decision.
Putin announced his decision in phone calls to the leaders of Germany and France, who voiced disappointment, the Kremlin said, and was later shown on state television signing the decree.
Moscow's move could torpedo a last-minute bid for a summit with U.S. President Joe Biden to prevent Russia from invading Ukraine, and the rouble extended its losses as Putin spoke on the issue, falling 3.3 per cent on the day to 79.83 per dollar.
Putin delivered a long televised address that ended with his announcement, delving into history as far back as the Ottoman empire and as recent as the tensions over Nato's eastward expansion - a key irritant for Moscow in the present crisis.
"I deem it necessary to make a decision that should have been made a long time ago - to immediately recognise the independence and sovereignty of the Donetsk People's Republic and the Luhansk People's Republic," Putin said.
He said earlier that "if Ukraine was to join Nato it would serve as a direct threat to the security of Russia."
Putin has for years worked to restore Russia's influence over nations that emerged after the collapse of the Soviet Union, with Ukraine holding an important place in his ambitions.
Russia denies any plan to attack its neighbour, but it has threatened unspecified "military-technical" action unless it receives sweeping security guarantees, including a promise that Ukraine will never join Nato.
Recognition of the rebel-held areas could pave the way for Moscow to send military forces into the two separatist regions - Donetsk and Luhansk - openly and argue that it is intervening as an ally to protect them against Ukraine.
A Russian parliament member and former Donetsk political leader, Alexander Borodai, has said that the separatists would then look to Russia to help them wrest control of the parts of the two regions that are still under the sway of Ukrainian forces.