The former Prime Minister appeared on Thursday's show to discuss Brexit and his life after Number 10 alongside his wife Samantha.
But when discussing Boris Johnson's use of the Vote Leave campaign bus emblazoned by the claim that leaving would mean £350 million a week extra for the NHS, Mr Cameron accidentally said the s-word which rhymes with "sat". Oops!
When Phil asked what he thought of the bus, David said: "I [bleep] at the..." before realising his mistake.
Holly and Phil burst out laughing as Phil said: "Did you? We all did!"
David said: "Sorry! I shouted at the TV."
As Phil and Holly descended into giggles, Mr Cameron tried to continue what he was saying.
He said: "It was incredibly frustrating.... sorry, [I meant] shout, shout!" as he laughed.
He added: "We've broken a new boundary. I'm very sorry."
Well, at least you've never said that on News Light!
Phil joked: "Well, at least you've never said that on News Light!"
Viewers were in hysterics over the slip of the tongue and shared their thoughts on Twitter.
One person said: "David Cameron said [bleep]," followed by a string of laughing face emojis.
Another wrote: "'I [bleep] at the TV' - must be nice to be rich enough to afford to have a telly in your bathroom!"
A third joked: "Today I learnt that David Cameron was so upset at the Leave campaign's bus of lies that he [bleep] at the TV."
Meanwhile, during the chat, the former Tory leader spoke about leaving his position as Prime Minister.
He said: "I wasn't happy to leave. I was desperately sad to leave and this sense that I had failed in the vital mission to keep us inside a reformed EU."
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