Updated February 21, 2023 at 10:48 AM ET

Following his surprise visit to Kyiv, President Biden will give a speech Tuesday to mark the anniversary of Russia's invasion of Ukraine.

Speaking from Warsaw, Biden will speak to how the United States has rallied western leaders to support Ukraine and stand united against Russian President Vladimir Putin.

"Putin thought Ukraine was weak and the West was divided," Biden said Monday in Kyiv, alongside Ukrainian President Volodymyr Zelenskyy. "As you know, Mr. President, I said at the beginning, he's counting on us not sticking together."

Biden's remarks are set to begin at 11:30 ET. Watch the speech below.

The speech comes hours after Putin gave his own address in Moscow — though the White House insisted the timing was coincidental.

Putin said the war in Ukraine was an existential struggle against the West, and claimed that sanctions had no effect on the country's economy. He also said he was suspending Russia's participation in the New START arms control treaty.

Biden is expected to cast the war as a battle between democracy and autocracy.

"What is at stake here is more than just the success and survival of the nation of Ukraine," Biden's national security adviser Jake Sullivan told reporters. Biden is expected to say the war has ramifications for "the rules-based international order, fundamental principles of sovereignty and territorial integrity, and the fundamental values of independence, democracy, freedom that matter so much to everyday American people," Sullivan said.

Biden's visit comes as the war enters a new phase

The visit to Ukraine and Poland comes at a critical time as the war enters a new and disconcerting phase. Russia has launched its latest spring offensive. Ukraine is expected to soon mount its own counteroffensive — with the assistance of U.S. and western weapons. And the end of the war is nowhere in sight.

Biden's visit will seek to reassure the region that U.S. support remains strong, while sending a message back home that the U.S. needs to remain united behind Ukraine.

Biden will also meet Polish President Andrzej Duda as well as leaders of eastern flank allies known as the "Bucharest 9."

Poland is a close NATO ally and has provided $3.8 billion in military and humanitarian assistance. Kirby said Biden will also use the opportunity to thank Poland for hosting U.S. forces.

Biden has insisted he will not send U.S. troops to Ukraine. But he's been equally adamant that the United States was prepared to defend NATO members.

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