Former Secretary of State John Kerry ripped President Donald Trump during an interview Friday night with "Real Time" host Bill Maher.

While promoting his memoir, "Every Day Is Extra," Kerry responded to a tweet from Trump that suggested he had "illegal meetings" with the Iranian regime.

John Kerry had illegal meetings with the very hostile Iranian Regime, which can only serve to undercut our great work to the detriment of the American people. He told them to wait out the Trump Administration! Was he registered under the Foreign Agents Registration Act? BAD! — Donald J. Trump (@realDonaldTrump) September 14, 2018

He blasted the president with numerous statements, in one instance saying that Trump seems to care more about "his Twitter likes" than he does the Constitution.

"He's got the maturity of an 8-year-old boy with the insecurity of a teenage girl," Kerry said.

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Kerry had also responded to Trump's tweet blasting him earlier on Friday, saying he should be more concerned about his former campaign chair Paul Manafort meeting with the special counsel.

Mr. President, you should be more worried about Paul Manafort meeting with Robert Mueller than me meeting with Iran's FM. But if you want to learn something about the nuclear agreement that made the world safer, buy my new book, Every Day Is Extra: https://t.co/DKjc33Kvvu https://t.co/cesltkt0zW — John Kerry (@JohnKerry) September 14, 2018

Former Secret Service agent Dan Bongino reacted to the remarks Saturday on Fox & Friends, saying that the former secretary of state's comments were offensive.

"I have a teenage daughter. What's he trying to say? At least my teenage daughter doesn't park her boat in Rhode Island to avoid Massachusetts taxes," he said.

He also criticized Kerry's meetings with Iran, questioning how former National Security Advisor Michael Flynn is being tried for allegedly violating the Logan Act.

Some have suggested that Kerry's meetings with Iranian Foreign Minister Javad Zarif violate the Logan Act, which prohibits private citizens from negotiating on behalf of the United States without being authorized.

.@dbongino: “How is John Kerry not guilty of a Logan Act violation?” pic.twitter.com/4rStvpgJ6K — Fox News (@FoxNews) September 15, 2018

"Do the rules exist anymore?" Bongino said.

Watch more from Fox & Friends above, and see Kerry's interview with Dana Perino on The Daily Briefing below.

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