'Masked Singer' : Ken Jeong Felt 'Upset' and 'Disrespected' by Rudy Giuliani Reveal, Says Sources

Rudy Giuliani was unmasked during a recent taping of the Fox competition series

Ken Jeong was not happy with The Masked Singer's choice to cast Rudy Giuliani as a contestant, a source close to the set tells PEOPLE.

During last week's taping of the Fox series' season 7 premiere, former New York City mayor Rudy Giuliani was unmasked as one of the contestants, Deadline first reported.

After Giuliani was revealed as the contestant, Jeong, 52, and fellow judge Robin Thicke both walked off the stage, according to the outlet. The other judges, Jenny McCarthy and Nicole Scherzinger, reportedly remained on stage after the reveal, where they briefly chatted with Giuliani, who is also former President Donald Trump's former attorney.

"Ken was super upset and indeed stormed out," the source says. "Robin actually followed him because he and Ken are very close friends and he wanted to check on him. Robin didn't storm out because of Giuliani."

A second source tells PEOPLE that Jeong felt "disrespected" by the decision to have Giuliani participate in the show.

"Ken felt disrespected and was livid to see Rudy was under the mask which is why he walked off. There's no way he could hide his feelings," says the insider.

The insider adds that Jeong — who earned his medical degree from the University of North Carolina at Chapel Hill and practiced medicine for several years in Los Angeles — has long expressed his political views, which are in direct opposition of Giuliani.

"Ken has been incredibly vocal about how the previous administration handled many things but especially COVID-19 and has found a lot of what they've said not only wrong but dangerous," says the insider. "To get someone who helped to spread misinformation and call into question the accuracy of our election and democracy to appear on his show was going to set him off."

Reps for The Masked Singer had no comment when reached by PEOPLE. A rep for Jeong did not immediately respond to PEOPLE's request for comment.

Efforts to reach Giuliani were unsuccessful.

Araya Doheny/WireImage; Roy Rochlin/Getty

Giuliani, 77, has been a controversial figure throughout his career in politics, but has faced particular scrutiny since his time serving as the personal attorney for Trump.

Last year, Giuliani's home and office were raided by federal agents during an investigation into his work in Ukraine. "Mr. Giuliani respects the law, and he can demonstrate that his conduct as a lawyer and a citizen was absolutely legal and ethical," his lawyer said in a statement after the raid, according to the Associated Press.

In June 2021, he was suspended from practicing law in New York by an appellate court that said he made "demonstrably false and misleading statements" about Trump's 2020 election loss to Biden.

Rudy Giuliani. SAUL LOEB/AFP via Getty

His erratic behavior in recent years has also raised eyebrows, including the viral video of him sweating profusely during a Trump press conference, his infamous appearance in Borat Subsequent Moviefilm as well as the time he was filmed shaving his face while seated in an airport restaurant.

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Giuliani is not the first politician to be a contestant on The Masked Singer, which is set to return for its seventh season on Fox on March 9.

In March 2020, former Alaska governor and one-time VP hopeful turned TV personality Sarah Palin was unveiled as the Bear during the show's third season.