But despite several reports the pair are no longer on speaking terms, the duo have made a heartwarming social media post squashing the rumours.
Taking to Instagram, 56-year-old television host shared a selfie that featured the pair smiling as they dined at a harbour-side restaurant in Sydney.
'The best lunch today with this guy...' Lisa captioned the photo.
Lisa's husband Peter FitzSimons also shared a shot of the pair to Twitter, holding up his book, Burke and Wills.
He captioned, 'This is the story of two intrepid adventures who came to a surprising end. And Karl and Lisa discussed it over lunch today!'
The two popular TV hosts spent more than a decade on air together before Lisa's shock resignation a fortnight ago.