Jon Stewart made a surprise appearance on The Late Show and had a blunt message to President Donald Trump.

Springing from underneath Stephen Colbert‘s desk, Stewart decided to address the president directly.

“I know you’re upset about all the criticism you’ve been taking and the ‘fake news’ and the ‘fake late night shows.’ It’s just, we’re still having a little trouble adjusting to your presidency as it goes into its 500th year,” Stewart said to Trump. “Everything’s off its axis. It’s a little unusual. Apparently, Vladimir Putin and Kim Jong Un are noble, intelligent role models, and Canada’s a bunch giant ***holes. Like that’s hard to get used to. You’re redoing the post-war alliances, only this time… we’re with the Axis powers. I just want to say there’s one hallmark to your presidency that I we’re finding the most difficult is that, no matter what you do, it always comes with an extra layer of gleeful cruelty. And dickishness.”

“It’s not just that you don’t want people taking a knee, it’s that they’re ‘sons of bitches’ if they do. It’s not just denying women who accuse you of sexual assault, it’s saying ‘they were too ugly anyway.’ You can’t just be against the media, they’re ‘enemies of the people,'” Stewart continued. “It’s not even partisan. Anyone in the Republican Party dare speaks against you, they also must be humiliated, even if they have a terminal disease. Which brings us to immigration…. Boy, you f**ked that up!”

The former Daily Show host told Trump he “made his point” about enforcement of immigrations laws but he injected “villainy” when separating the families of illegal immigrants.

“It made me realize something. You may be orange, you may like hamburgers, you may be a clown, but you are no Ronald McDonald,” Stewart quipped.

“Clearly, we’re not going to be able to negotiate or shame you into decency, but there is one place where I draw the line: I won’t allow you and your sycophants to turn your cruelty into virtue,” Stewart warned the president. “And what Donald Trump wants is for us to stop calling his cruelty and fear and divisiveness wrong but to join him in calling it right. And this we cannot do.”

Watch the clip above, via CBS.

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