U.S. President Joe Biden on Saturday slammed Russian President Vladimir Putin following the invasion of Ukraine, while rallying countries to support Kyiv in what he believes to be part of a larger fight between democracies and autocracies.

"We must commit now to be in this fight for the long haul. We must remain unified today and tomorrow and the day after, and for the years and decades to come," Biden said in a speech in Warsaw that wrapped up his four days in Europe to affirm with leaders of the West their unity in responding to Russia's aggression.

"Ukraine will never be a victory for Russia -- for free people refuse to live in a world of hopelessness and darkness," Biden said. Referring to Putin, he added, "For God's sake, this man cannot remain in power."

U.S. President Joe Biden makes a speech in Warsaw on March 26, 2022. (Kyodo)

A White House official immediately denied that Biden's remarks were meant to be a call for regime change, which could further add to tension between Washington and Moscow.

"The president's point was that Putin cannot be allowed to exercise power over his neighbors or the region," the official said.

Biden's trip to Belgium and Poland came exactly one month after Russia began its military campaign against its neighboring country where cities have been reduced to rubble, the civilian death toll continues to rise and the humanitarian crisis has forced millions to flee.

In his nearly 30-minute speech at the Warsaw Royal Castle in Poland, Biden called the war a "strategic failure" for Moscow, which is facing stiff resistance from the people in Ukraine and a more united West that is beefing up defense against Russian threat and is unleashing massive sanctions to cripple the Russian economy.

"In fact, Russia has managed to cause something I'm sure he never intended," Biden said. "The democracies of the world are revitalized with purpose and unity found in months that we'd once taken years to accomplish."

From the beginning of his administration, Biden has been rallying democracies around the world to counter autocracies such as China and Russia. Support for Ukraine has also come from some key U.S. allies in the Asia-Pacific, such as Japan that believes any tolerance of a change in the status quo could embolden Beijing, which has been increasing its assertiveness in the region.

Biden said Saturday that the fight to defend freedom could be costly, but that it is "a price we have to pay" because "the darkness that drives autocracy is ultimately no match for the flame of liberty that lights the souls of free people everywhere."

Russia began its military attack against Ukraine on Feb. 24 after asserting that its security was under threat from the North Atlantic Treaty Organization's eastward expansion and the possibility of Ukraine joining the security alliance.

Putin has also insisted that he is carrying out a "special military operation" to "demilitarize and denazify" Ukraine, even though Ukrainian President Volodymyr Zelenskyy is a Jew whose relatives were victim of the Nazi Holocaust. The United States and its allies have labeled Putin's war as unjustified and unprovoked.

The Biden administration has maintained it will not send American troops in Ukraine, warning that being drawn into a direct conflict with nuclear-armed Russia would result in "World War III."

But the United States, along with other NATO member countries, has provided security assistance to Kyiv so that it can help defend itself. Ukraine has also received humanitarian assistance from the United States and other countries.

Iruna Manachin, a 38-year-old mother of three children who fled from Ukraine to adjacent Poland, said she had no idea when she can return home, but that her hope is that the war is "stopped."

Poland is a NATO member seen at the forefront of defense efforts to repel any further Russian invasion beyond Ukraine. It has already accepted over 2 million of the some 3.8 million who have fled Ukraine, according to data by a U.N. refugee agency.

The Biden administration, meanwhile, has reiterated the U.S. commitment to NATO's collective defense agreement, which means that a Russian attack of any NATO member country could trigger a direct U.S. involvement.


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