Russian President Vladimir Putin recognized 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% 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.

EU: We will react with firmness and determination

There's been swift condemnation of the Russian move.

"The recognition of the two separatist territories in Ukraine is a blatant violation of international law, the territorial integrity of Ukraine and the Minsk agreements," said Ursula von der Leyen, the European Commission's president, referring to peace agreements covering eastern Ukraine.

"The EU and its partners will react with unity, firmness and with determination in solidarity with Ukraine."

The apparent recognition of breakaway regions of eastern Ukraine by Russian President Vladimir Putin is a breach of international law, British Prime Minister Boris Johnson said on Monday.

While Johnson was speaking, Putin signed a decree recognising the independence of the two breakaway regions of Luhansk and Donetsk regions, which broke away from Kyiv's control in 2014.

"I gather just as I came into this press conference that Vladimir Putin has effectively announced that Russia is recognising the breakaway republics of Donetsk and Lugansk. This is plainly in breach of international law. It's a ... flagrant violation of the sovereignty and integrity of Ukraine," Johnson told a press conference.