A top US official on Tuesday described President Vladimir Putin's accusations that Russia had been threatened by the West as justification for invading Ukraine as "absurdity".
"Nobody is attacking Russia. There's a kind of absurdity in the notion that Russia was under some form of military threat from Ukraine or anyone else," White House National Security Advisor Jake Sullivan told reporters.
Speaking hours ahead of President Joe Biden delivering his own speech in Warsaw to mark the anniversary of Putin launching the war, Sullivan said the Kremlin leader was the aggressor.
"This was a war of choice. Putin chose to fight it. He could have chosen not to. And he can choose even now to end it, to go home," Sullivan said.
"Russia stops fighting the war in Ukraine and goes home, the war ends. Ukraine stops fighting and the United States and the coalition stops helping them fight - then Ukraine disappears from the map," he added.
Previewing Biden's speech, Sullivan said he would not "sketch out in any kind of specifics, a vision of a diplomatic end to the war."
Rather he will focus on the broader lesson of Ukraine in what he sees as an "inflection point" in a global struggle between democracies and autocratic regimes.
"So his remarks will speak specifically to the conflict in Ukraine, but of course, they will also speak to the larger contest at stake between those aggressors who are trying to destroy fundamental principles and those democracies who are pulling together to try to uphold it."
Biden is due to deliver his own speech at around 1630 GMT following talks with Polish President Andrzej Duda, who has been a key advocate for support for Ukraine within the EU and NATO and a day after a surprise visit to Kyiv.