Russian President Vladimir Putin has received a standing ovation in parliament after defending Crimea's breakaway vote to join Moscow.

To regular applause during a televised address to the nation, he pointed out that 82% of Crimea's residents turned out for Sunday's referendum, and more than 96% of them voted to join Russia.

He said the vote was "quite convincing" and was held "in full accordance with democratic procedures and international legal norms".

"The (Crimean) issue has a vital importance, a historic importance for all of us," he said.

US Vice President Joe Biden, who has arrived in Poland for a two-day trip through Eastern Europe, dismissed Russia's actions as "nothing more than a land grab".

America and its G7 allies - Britain, Germany, Canada, France, Japan and Italy - will gather next week at The Hague to discuss "further steps they may take" against Russia.

Mr Putin said he did not want to "carve up" Ukraine, but said the West had "crossed a line" with its behaviour over the former Soviet country.

"They are trying to drive us into a corner," he told a joint session of parliament in Moscow.

He also accused the West of hypocrisy, pointing to Kosovo's bloody independence from Serbia, which was backed by the West and opposed by Russia.

His speech came as he signed a treaty making Crimea officially part of Russia. It coincided with a mass rally, celebrating ties between Russia and Crimea, in Moscow's Red Square.

Mr Putin also thanked Ukraine's soldiers for "not staining themselves in blood in Crimea".

He said the peninsula's future was decided without a shot being fired because it was "practically impossible to fight the will of people."

Western leaders say Crimea's vote was illegal and have imposed travel bans and asset freezes on senior Moscow officials.

British Prime Minister David Cameron said Russia's actions "are in flagrant breach of international law and send a chilling message across the continent of Europe."

After Mr Putin spoke, British Foreign Secretary William Hague tweeted: "Preparatory work is now underway for a third tier of sanctions, including economic and trade measures."

Meanwhile, one of Ukraine's top politicians told Sky News his country is ready to fight if Russian soldiers cross the border from Crimea into mainland Ukraine.

Serhiy Taruta, governor of the eastern city of Donetsk, warned: "We're going to have a war. Our people will take up arms and they will protect our country."

Under the Russian treaty, Crimea will ditch Ukraine's currency, the Hryvnia, and adopt the Rouble next month.

It is also due to move time zones - adopting Moscow time, which is two hours ahead of Kiev - on March 30.

The peninsula is also offering Crimean soldiers the chance to join the Russian army.