During an appearance on CBS' "Late Show with Stephen Colbert" on Monday, former Secretary of State Hillary Clinton took issue with his handling of the phone call between President Donald Trump and Ukrainian President Volodymyr Zelensky that helped prompt an impeachment inquiry.

"How many times, when you were secretary of state, did you have to say to Barack Obama, 'You can't extort foreign countries to get dirt on your political enemies'?" Colbert jokingly asked Clinton.

"Yeah, that never happened," Clinton replied, laughing.

"The secretary of state's job is to make sure that he knows, number one, what the president is going to say on those calls," she said. "These are usually highly prepared calls."

According to media reports, Secretary of State Mike Pompeo was one of the officials who listened in on Trump's call in which the president asked Zelensky to investigate former Vice President Joe Biden and his son, Hunter Biden.

"If the secretary of state was on the call, as is now being reported, he should have been one of the very first people to just say, 'Wait a minute, we have to clean this up. You can't let that stand.'" Clinton said. "But we don't know what he did."

Colbert asked how she would have reacted – when she was America's top diplomat – to the president sending out his personal attorney to "handle foreign policy," a nod to Rudy Giuliani's admission that he contacted Ukrainian officials at the direction of the State Department.

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"Presidents often use – as do secretaries of state – they might use an envoy or a special adviser to deliver a message," she said. "But again, it is supposed to be carefully thought through. And from what we’ve seen on television, carefully thinking through is not one of Rudy’s strong points."

Clinton appeared on the "Late Show" with her daughter Chelsea Clinton to promote their new book, "The Book of Gutsy Women: Favorite Stories of Courage and Resilience." Colbert warned that the book would have to be discussed later in the segment because it was "Ukraine week" and an impeachment inquiry was underway.

"Is it time to – dare I say – lock him up, lock him up?" Colbert asked, beginning to pump his fist.

"Lock him up," the crowd began to chant.

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Clinton said an impeachment inquiry to examine the evidence was "exactly what should be done."

She said this alleged abuse of power by Trump was resonating with voters.

"We've known for a long time that he was a corrupt businessman who cheated people. And we've known that he and his campaign asked for aid from Russia. We've known that," she said. "But to see him in the office of the president, putting his own personal and political interests ahead of the national security of our country, just pierced through whatever confusion or denial people had."

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