Stephen Colbert fires away at Trump: 'You're a bad president. Please resign.'

Stephen Colbert called for President Donald Trump to step down after a report that he had revealed highly classified information to Russian diplomats.

"The good news? Trump found the leaker," Colbert joked during Monday's "Late Show" opening monologue of the president's search for those who have been leaking information to the media.

On Monday, The Washington Post reported that Trump had revealed classified information about an "Islamic state terrorist threat" while meeting with the  Russian foreign minister and ambassador last week. White House officials have since refuted the report. Secretary of State Rex Tillerson said, "During that exchange, the nature of specific threats were discussed, but they did not discuss sources, methods, or military operations."

Meanwhile, the reaction to the reported sharing of classified information has been swift and harsh. Legal expert Alan Dershowitz said, "This is the most serious charge ever made against a sitting president."

One US official told the newspaper that the reportedly leaked details are considered "code-word information." 

In an effort to explain what that means to his audience, Colbert offered some examples: "The package has been delivered. The squirrel is in the basket. The idiot is in the Oval. It could mean anything. We don't know what that means."

Pending more information on the reported leak by Trump, Colbert pivoted to the ongoing controversy surrounding the president's firing of FBI Director James Comey. The host focused on Trump's recent tweet, a vague threat suggesting he would release tapes of conversations he had with Comey if the former FBI chief began to leak details to the media.

"That would be huge. It would be the first time a leaked tape made Donald Trump look good," Colbert said, a reference to the video that leaked before the 2016 election showing Trump lewdly boasting about his aggressive sexual advances toward women.

Amid the fallout over Comey, Trump has reportedly been unhappy with his staff and has been considering replacing key members in what has been referred to as a "reboot." But Colbert made a plea to keep White House Press Secretary Sean Spicer, a frequent source of entertainment for the host.

"I have something to say here. Donald Trump, if you're watching, first of all: You're a bad president. Please resign," Colbert said. "Second, please, please, please don't take Sean Spicer from us! Where am I going to get my daily dose of veiled anger and condescension?"

Watch Colbert's monologue below: