As he delivered his first State of the Union address to a joint session of Congress and the American people, praising the Ukrainian "wall of strength" that has stood tall against Russian invaders, Biden made clear there would be no US boots on the ground in the week-old war on Europe's doorstep.

"Let me be clear: our forces are not engaged, and will not engage, in the conflict with Russian forces in Ukraine," the Democratic leader said.

Biden nevertheless leveled ferocious criticism at Putin.

"A Russian dictator, invading a foreign country, has costs around the world," Biden said.

"In the battle between democracy and autocracy, democracies are rising to the moment, and the world is clearly choosing the side of peace and security."

The West, led by tough new steps from Washington, has launched a fierce economic battle with Russia, unleashing a wave of sanctions that threaten to bring the Russian economy to its knees. 

Taking aim at Russian oligarchs and "corrupt leaders" who Biden said have bilked billions of dollars off Putin's regime, the US president delivered a stern warning that the West will "seize their yachts, their luxury apartments, their private jets."

"We're coming for your ill-begotten gains," Biden said to applause.

Biden went on to announce a ban on all Russian aircraft from US airspace, adding the United States to Canada and a host of European nations closing airspace to Russian airliners and other aircraft in response to the invasion of Ukraine.

Putin, he said, had badly underestimated the powerful response his invasion would illicit from Western nations as sanctions inflict "pain" on Russia's economy.

"Putin's war was premeditated, totally unprovoked," he said.

"He rejected repeated efforts at diplomacy. He thought the West and NATO wouldn't respond. He thought he could divide us at home," Biden said. "He thought he could divide us in Europe as well."

"But Putin was wrong. We are ready. We are united."

Biden paid particular praise to Ukrainians who faced off against Russians despite an overwhelming military assault.

Putin "thought he could roll into Ukraine and the world would roll over. Instead, he met with a wall of strength he never anticipated or imagined," Biden intoned. "He met the Ukrainian people."

In a moment of bipartisan unity, US lawmakers gave a standing ovation to Ukraine, turning to the country's ambassador to Washington, Oksana Markarova, who was seated in First Lady Jill Biden's VIP box