The 43-year-old comedian – who is played by Leigh Francis – admitted the Loose Women panellist wasn’t her usual no-nonsense self on the programme in 2008.
When asked by Mirror Online who the “worst” guest he’s had on the show in terms of banter, he said: “She was so quiet. She was like, ‘Go on then, keeping taking the p**s out of me’ – but we were only having a laugh.
“I’m not saying she was horrible but we want people on the show to have fun!”
However, the flame-haired funnyman is desperate to get the 38-year-old star back on the panel after watching her let rip with her opinions on Loose Women.
He said: “She’s definitely not quiet on there [Loose Women], is she? Katie was on Celebrity Juice ages ago but I think she’s more relaxed now. She’s let her guard down.
“I enjoy watching her on Loose Women so it would be nice if she could come back … and hopefully be a little more fun!”
The new series of Celebrity Juice is set to hit screens on Thursday night but Keith never knows who producers have got lined-up as guests.
He said: “I’m only messing around when I joke with people. I’m not vindictive.
“They tend to give as good as they get so I don’t think anybody would ever walk off of my show. It’s all in jest.”