Capital Radio's alternative London radio station Xfm has appointed a new programme controller after Andrew Phillips agreed to leave the company after four years.

The Xfm head of music, Andy Ashton, 32, will take over the role of Mr Phillips, who had been on sick leave for several weeks after injuring his foot.

The station, which fought against formidable opposition to get a licence from the Radio Authority, started out as an independent music channel backed by The Cure's Robert Smith.

But it was taken over by Capital in 1998 and, despite fears that its music policy of showcasing independent bands who could not get airtime on other stations would change, Xfm grew in popularity with an audience of more than 500,000 who tune in to shows from the likes of Ricky Gervais and Christian O'Connell.

However, the station's audience has not grown as quickly as Capital may have liked, and the replacement of the programme controller could hint at a revamp to attract more listeners.

"Xfm today confirms that following discussions with Andrew Phillips, it has been agreed that he will step down from his position as programme controller for the station and will leave the company," said a statement by Xfm.

Mr Phillips' departure ends weeks of speculation about his future at the station.

"In his four years with Xfm Andrew has been instrumental in repositioning Xfm as one of the most innovative and critically acclaimed stations in the UK... We wish Andrew continued success in what we are sure will be a successful future in the industry."

Mr Ashton, who joined Xfm as head of music in 2000, had been handling the programme controller's job in Mr Phillips' absence. A new head of music has yet to be appointed.

Mr Ashton said he was "absolutely thrilled" to be taking over and said he was "completely confident" that he and his new team "can deliver an even more exciting radio station for new music fans".

The Xfm managing director, Graham Bryce, said Mr Ashton "combines exceptional creativity and commitment as well as incredible attention to detail".

In a statement Mr Bryce said: "That, along with strong relationships with staff and presenters, is exactly what we need to deliver great radio and sustain audience growth for the station. Under his guidance I am confident that Xfm can deliver even more success in the coming year".

Karl Pilkington, who has worked for Xfm for five years, has been promoted to deputy programme controller. He will continue as head of production, including producing and co-presenting the Ricky Gervais and Stephen Merchant show on Saturday afternoons.

Broadcasting on the FM frequency in London, Xfm has an audience of 502,000 according to the latest Rajar figures.

Listeners across the UK tuning in via digital radio, Sky Digital and NTL, bring the station's total audience to 634,000 nationwide.

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