"I can't speak to how many camps or what they look like," Pentagon spokesman John Kirby told reporters when asked about statements from Kyiv that some 1.2 million Ukrainians were being sent to Russia and placed in camps.

"But we do have indications that Ukrainians are being taken against their will into Russia," Kirby said. He called these actions "unconscionable" and "not the behavior of a responsible power."

The deportation of Ukrainians from their own nation -- often to isolated or economically depressed regions of Russia, according to Kyiv -- is another indication that Russia's President Vladimir Putin "simply won't accept and respect Ukrainian sovereignty."

Ukraine's President Volodymyr Zelensky said back in early April, six weeks after Russia launched its deadly invasion, that thousands of Ukrainians had been sent to Russian territory.

But that figure has since ballooned to more than 1.19 million, including at least 200,000 children, Ukraine's ombudswoman Lyudmyla Denisova said.

Kirby stopped short of describing the deportations as ethnic cleansing, stressing it was not the Pentagon's place to make such determinations. But he said there was abundant evidence of "Russian brutality" during the war.

Moscow has had "75 days of brutalizing the nation of Ukraine and the Ukrainian people," he said. "And every time you think they just can't fall to a new low, they prove you wrong."