The pregnant star, who is expecting a baby with third hubby Kieran Hayler, was appearing on the breakfast show via telephone when she made the jibe about Peter's looks.
During the chat on The Kyle And Jackie O Show, host Kyle let slip that Jackie had gone to school with Peter in Oz and was "in love with him from a distance".
Katie jokingly replied: "Did you have the right eyeballs in? Did you have your right eyes on?"
Jackie went on to admit that she once went to Peter's house and spent the entire time staring at him, before Kyle joked that something had "happened under a blanket".
Katie told Jackie: "One thing you and me have in common, Jackie, we're not the only ones – he's probably had loads, so we should flatter ourselves really!"
During the interview, former glamour model Katie spoke about how "dramatic" her life is thanks to her exes, including cage fighter Alex Reid.
"Why do I always have dramas with the exes? Why don't they let me get on with it, like I let them get on with it?" she asked.
"They're always causing trouble but, on the flip side, I get to write books on it. So really they keep me busy."
Katie will fly Down Under for the official launch of her Australian shoe line, The Gold Collection, in October, once she has given birth.
She added that the baby would travel with her, but her other three children - Harvey, Junior and Princess - will have to stay in the UK due to their schooling.
Listen to the full interview here: