U.S. President Joe Biden said Tuesday the United States is united in support for Ukraine as it opposes a Russian invasion, and that the U.S. will stand with Ukraine 'as long as it takes.'

Speaking during his State of the Union address to a joint session of Congress, Biden said government united NATO, built a global coalition and stood against the aggression of Russian President Vladimir Putin.

Biden Strikes Optimistic, Determined Tone in State of the Union

The United States and other NATO allies have provided billions of dollars in military aid, including air defense systems, to bolster Ukrainian forces. U.S. and European Union sanctions have also sought to impose a financial cost on Russia.

Biden noted that his address to lawmakers last year came days after Putin launched what Biden called a 'brutal attack against Ukraine' and a test for the world.

'Would we stand for the most basic of principles? Would we stand for sovereignty? Would we stand for the right of people to live free from tyranny? Would we stand for the defense of democracy?' Biden asked.

Putin has criticized Western aid to Ukraine as being a threat against Russia, while saying Russia will prevail in Ukraine.

Ukrainian President Volodymyr Zelenskyy thanked Biden 'for the powerful words of support.'

'We are grateful for U.S. leadership in helping Ukraine, for solidarity of the entire U.S. people,' Zelenskyy tweeted Wednesday. 'Our values are the same, our common goal is victory.'