TalkTV host Morgan was a judge on the ITV talent show himself from 2007 to 2010 and had some positive words for the show on Saturday night - except for Walliams, who he has spoken about his dislike of before.
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Morgan, who used to judge alongside Simon Cowell and Amanda Holden who have now been starring in the show with Walliams and Alesha Dixon for 10 years, appeared to be watching it as he tweeted about the line-up.
He wrote: "Love the judging panel on @BGT - apart from David Walliams. All he does is drip & drool unctuously sycophantic drivel, and he’s soooooo creepy."
Although children's author Walliams, 50, has not hit back with his feelings on Morgan, 57, the former Good Morning Britain presenter has made no secret of his views on Walliams in the past.
In 2020 after head judge Cowell suffered a serious bike accident, Morgan told The Mirror he had been offered the chance to replace his old friend and step back into the Britain's Got Talent judging panel while he recovered - but couldn't bring himself to work with Walliams.
He said: "I do have conversations with BGT every now and again, particularly after Simon had his injury.
"But I couldn’t work with Walliams. I think he is a duplicitous, treacherous, piece of work.
"He is one of those people who says one thing to your face and then sticks it to you behind your back. If he was sitting there I wouldn’t be interested. But if he wasn’t sitting there, who knows?"
Earlier in the week, Morgan was forced to apologise to viewers of his Uncensored show on TalkTV after a trans activist called him "a c***" live on air during a debate about trans women competing in sport.
Morgan said: “I apologise again to all viewers who are listening to that. Unfortunately, a complete idiot."
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