Gordon Ramsay has issued an unreserved apology for likening an Australian TV presenter to a pig after a ticking off from his mother. The celebrity chef's comments, made during a live cookery demo in Melbourne on Saturday, prompted the country's prime minister Kevin Rudd to describe Ramsay as a "new form of lowlife". The Hell's Kitchen star was reported to have compared Tracy Grimshaw - the host of a current affairs show on which he had appeared the night before - to a pig. Grimshaw used her programme, A Current Affair, to hit back at the chef, branding him an "arrogant narcissist". After the 42-year-old chef's spokeswoman apologised on his behalf on Tuesday night, Ramsay went on television to say sorry in person, saying: "I've had my mum on the phone this morning. "When your mum rings you and it's a b******ing down the telephone, you start to get the picture. She was disgusted and she wanted to know what happened." Ramsay used the interview with Channel Nine to apologise directly to Grimshaw. He said: "Tracy, where do I start? First of all, you've shown me great respect and amazing support over the last three or four years and I'd just like to take this opportunity to apologise for the stupid comments and am deeply mortified that the whole thing has gone this far. My apologies." On her show, Grimshaw complained that the remarks were unprovoked, and she found them hurtful. "We all know bullies thrive when nobody takes them on," she said. "And I'm not going to let some arrogant narcissist bully me. Obviously Gordon thinks that any woman who doesn't find him attractive must be gay. For the record, I don't and I'm not."