Tarbuck bows out of 'Big Breakfast'

The future of Channel 4's Big Breakfast show was uncertain yesterday after Liza Tarbuck told fans she will step down as co-host this summer. The programme is now looking for its fourth female presenter in less than three years.

The 34-year-old daughter of the Liverpudlian comedian Jimmy Tarbuck will leave the show at the end of August, she told fans in an online chat. A programme spokesman said: "Liza has done a year with the show, and she wants to get back into acting, as she said in her Web chat." The spokesman could not confirm reports that she was leaving because of her growing weariness of the early morning starts or of a reported falling-out with show managers.

But viewing figures have failed to reach the heights of its Chris Evans/Gaby Roslin days and are now less than half its GMTV rival. Analysts say the success of the show is "almost entirely" down to the chemistry between its presenters. The show rallied with the pairing of Johnny Vaughan and Denise Van Outen, but after she left for other projects there was a much-criticised stint with the model Kelly Brook.

She was sacked, and Liza Tarbuck was widely considered a worthy sparring partner for Vaughan. But she has failed to halt the programme's decline. Vaughan has long been rumoured to be considering offers in the United States.