Stephen was hosting the Britain’s Got Talent spin-off when he asked the judging panel to award a new position of power on the show alongside Simon Cowell.
He asked: “Who would be the Britain’s Got Talent deputy judge?”
While Amanda Holden and Alesha Dixon both wrote down “me” and chose themselves, David opted for another answer.
David wrote: “Amanda. (Because they did it).”
Stephen ignored the second part of the statement when it read it aloud, but Alesha gasped in horror.
Amanda was in hysterics, but Simon jumped up from his seat in a rage.
He ranted: “David, you’ve actually crossed the line!
“You really are a smutty little man, aren’t you? Get out!”
David seemed to be pushing ever closer to the line after Simon told viewers last night that David was “un-sackable”.
Simon was not impressed at all by David’s suggestion and gave him a stern telling off, prompting David to make a swift exit.
As the show went to an advert break, viewers could see Simon storm over to David to have a stern word.
Fans of the show instantly took to social media following the shocking moment.
One viewer tweeted: “#BGMT @davidwalliams definitely pushing the statement @SimonCowell said last night about him being ‘unsackable’ I thought it was hilarious but Simon definitely didn’t. Be surprised if he’s on tomorrow night.”
“It was at this moment Simon realised he shouldn’t have told David he was unsackable last night. #BGT #BritainsGotTalent #BGMT,” posted another.
A third added: “OH MY. If Simon’s looks could kill! David would be a gonner!”
“I think Simon staring down the camera next to David and telling him ‘you’ve crossed the line’ in such a serious manner has actually made me s**t myself for David. #BGT #BritainsGotTalent #BGMT,” wrote another.
A fifth simply noted: “Simon is Livid #BGMT,” as another said: “Simon really looked p**sed off at David #BGMT.”
One fan didn’t know what to make of the situation, tweeting: “Can’t tell if @SimonCowell is genuinely annoyed at @davidwalliams or not!
“I’ve never seen Simon look so shocked! #BGT2018 #BGMT @StephenMulhern.”
Britain’s Got More Talent continues tomorrow on ITV2 at 10pm.