In a speech later on Monday, US Vice President Joe Biden is anticipated to outline his perspective on the conflict in Ukraine as a struggle for democracy.
As part of his three-day trip, he will deliver his speech in Warsaw, the capital of Poland.
It will happen shortly after the Russian president accused the West of starting the war.
Mr. Biden unexpectedly traveled to Ukraine on Monday to reaffirm Washington's support for Kyiv.
Days before the first anniversary of Russia's total invasion of Ukraine, both leaders give competing speeches.
The US president is anticipated to emphasize in Warsaw the crucial role that the US played in rallying western support for Ukraine against Russian aggression.
However, he will also be attempting to increase domestic support for his policy, as some politicians have expressed skepticism regarding the extent of US involvement.
Vladimir Putin, the president of Russia, delivered his annual state of the nation address earlier on Tuesday. In it, he accused the West of being hypocritical and abandoning "fundamental agreements.".
To thunderous applause, he declared, "I want to repeat: it is them who are responsible for the war, and we are using force to stop it.".
Additionally, Mr. Putin repeated his erroneous assertion that Kiev had been posing a Nazi threat to Moscow, which he used as justification for starting his "special military operation.".
Prior to his speech, US President Joe Biden will meet with Andrzej Duda, the president of Poland, and other central European allies to talk about bilateral cooperation and bolstering NATO's ability to deter aggression.
After meeting with his counterpart from Ukraine, Volodymyr Zelensky, in Kyiv on Monday, the president stated at a press conference that the US will support Ukraine for "as long as it takes.".
We are absolutely certain that you will continue to win, he said.
In the nine years since Russia annexed Crimea and its proxies took control of some of the eastern Donbas region, the two also paid a visit to a memorial to soldiers who lost their lives in action.
Following the visit, US Secretary of State Antony Blinken unveiled a new $450 million (£373 million) security assistance package for Ukraine as well as an additional $10 million in emergency support for the country's energy infrastructure.
Later this week, additional sanctions will be introduced against people and organizations "that are trying to evade or backfill Russia's war machine.".
One of Ukraine's strongest allies, the US has already provided military support worth billions of dollars.
Despite repeated requests from Ukraine for fighter jets, Mr. Biden recently announced that the US would send 31 battle tanks and longer-range missiles instead.
On the other hand, Mr. Zelensky claimed on Monday that he had spoken with Joe Biden about the potential for the US to send additional weapons.