Russia's invasion of Ukraine has destroyed cities and killed thousands of civilians. Millions more have fled. Now, the US president says these attacks amount to a "genocide."

Joe Biden used the term for the first time on Tuesday while announcing a new energy policy.

His office has been forced to dial back some of Biden's recent comments on Russian President Vladimir Putin, whom he describes as a war criminal.

Biden later told reporters he stands by his latest words.
He said, "The evidence is mounting. A bit different than it was last week. But more evidence is coming out of, literally, the horrible things the Russians have done in Ukraine."

Ukrainian President Volodymyr Zelenskyy didn't take long to react. He referred to the remark as "true words of a true leader."

Zelenskyy praised his security service for detaining the Kremlin's most high-profile political ally in Ukraine.

Fugitive Viktor Medvedchuk is the former leader of a pro-Russian opposition party and a close associate of Putin.

Zelenskyy said, "If Medvedchuk chose to wear a military uniform himself, he should come under war time rules. I propose to Russia to exchange their guy for our men and women in Russian captivity. It's important that our law enforcement and military agencies consider this possibility."

These developments come amid accusations that Russia may have used chemical weapons in the southeastern city of Mariupol.

Ukrainian forces say some people were struggling to breathe because of what they described as "poisonous substances of unknown origin."

Zelenskyy called on world leaders to react to these claims.

The US Secretary of State says Washington cannot confirm what happened. It's working with allies to find out.

Antony Blinken said, "We had credible information that Russian forces may use a variety of riot control agents, including tear gas mixed with chemical agents."

A spokesperson for Russian-backed separatist forces denied chemical weapons had been used in Mariupol.
But he had earlier hinted his side might use them.

Russian President Vladimir Putin said, "Our special military operation is going as planned. I am carefully watching the discussions at home and abroad. We shall not hide anything from the public."

Putin says the operation will continue until its "full completion" as peace talks have reached a "dead end."

British newspaper The Times has reported Putin dismissed about 150 officials of the Federal Security Bureau and arrested some of them.

The paper says they appear to have provided the Kremlin with misinformation about the situation in Ukraine before the invasion.