Jon Stewart Mocks Donald Trump Following Jimmy Kimmel Suspension

Jon Stewart is using heavy sarcasm to rip into Donald Trump ... this on the heels of Jimmy Kimmel getting suspended by ABC over his remarks about Charlie Kirk's killer.

"The Daily Show" host made an unusual appearance on the show Thursday -- he's typically only behind the desk on Mondays -- as the show rolled out a complete makeover, poking fun at the president.

Before Stewart appears in a Trump-like outfit against a golden decor backdrop ... the show's announcer says, "From Comedy Central, it’s the all-new government-approved ‘Daily Show’ with your patriotically obedient host, Jon Stewart."

The comedian pretends to be anxious as he tells the crowd, “We have another fun, hilarious, administration-compliant show” ... then rips NYC as a "crime-ridden cesspool" and even suggests the National Guard should invade the city.

After trolling Trump's recent trip to the UK ... Stewart dives into the Kimmel controversy, saying the First Amendment is now judged by a "talent-o-meter" -- which he calls a "scientific instrument that is kept on the president’s desk." He jokes if a performer isn't being nice to the president, the FCC will be notified.

Stewart quips he's not familiar with "Johnny Drimmel Live" but "our great nation has laid out very clear rules on free speech."