Iain, 44, delivered today’s Entertainment report in place of Good Morning Britain regular, Richard Arnold.
After unveiling Elton John’s new star-studded album, he moved on to discuss Dawn French’s dating advice.
The Vicar of Dibley star, 60, has told fans they should ditch “underwear that’s going to impress” in favour of Bridget Jones style “big pants”.
Iain seemed to agree with her, and unleashed another rant on the matter.
He told Kate and co-host Charlotte Hawkins: “What is this fashion about bikinis where they go right up?
“Hungry bums!” he laughed, as he discussed the thong-style of pant.
Kate, 50, and Charlotte, 42, gasped at the hilarious quip and instantly started to giggle.
Iain added: “I don’t know if we can say that on breakfast TV.”
The latest comes after yesterday’s appearance on Good Morning Britain which left Susanna Reid stunned following a Jim Davidson snub.
Iain paid tribute to the late Jim Bowen, who died earlier in the week aged 80.
However, as he read out various tweets in honour of the Bullseye host, it seemed he didn’t want to read out one from Jim.
Iain said: “Paddy McGuinness tweeted, and Jim Davidson tweeted – but I’m not interested in him.”
Susanna asked: “Why not? He’s one of those comedy legends.”
Iain retorted: “Let’s not.
“Let’s have this debate elsewhere.”
Good Morning Britain airs weekdays on ITV from 6am.
