Story highlights In an interview released Saturday, Trump said: "We've got a lot of killers"

McCain called Putin a "butcher" and a "thug"

Washington (CNN) Sen. John McCain on Tuesday delivered a fiery, not-so-subtle rebuttal to President Donald Trump's argument that the United States and Russia are morally equivalent, at one point slamming his hand on a lectern in condemning the Russian regime.

The Arizona Republican was speaking about Russian critic and deputy leader of the Freedom Party Vladimir Kara-Murza, who's recently been hospitalized in Russia. His lawyer believes he was poisoned.

"Vladimir knew that (Russian President Vladimir) Putin is a killer. And he's a killer. And he might very well be the next target. Vladimir knew there was no moral equivalence between the United States and Putin's Russia," said McCain, who's long been a fierce critic of Trump's rhetoric about Russia.

"I repeat," he continued, veering away from his prepared remarks and hitting the wooden lectern to underscore his point. "There is no moral equivalence between that butcher and thug and KGB colonel and the United States of America, the country that Ronald Reagan used to call a shining city on a hill. And to allege some kind of moral equivalence between the two is either terribly misinformed or incredibly biased. Neither can be accurate in any way."

McCain listed a number of other Putin critics and journalists who've allegedly been killed by the Russian government.

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