Mark Goodier, one of BBC Radio 1's longest-serving DJs and presenter of the Top 40 show is to leave his job on his 15th anniversary at the station.

The Sunday evening chart rundown that he presents will also get a revamp when he leaves.

Goodier says Radio 1 is now a "very cool, young station"

But Radio 1 denied he has been fired because of falling listener figures, saying his contract is coming to an end.

"He is due to leave on his 15th year anniversary, which is at the end of the year," a spokesman told BBC News Online.

"That's always been the case and has been the case for some time."

Goodier presented his first show on Boxing Day 1987, and has seen huge changes at the station.

The only DJs to have been at the station longer than him are John Peel and Annie Nightingale, who started in 1967 and 1970 respectively.

I've had a great time at Radio 1 but felt that my 15-year anniversary was a good time to move on

Mark Goodier

The search for a replacement is "an ongoing process", according to the spokesman, who said he hoped to have more news in the autumn.

"A new-look chart show will begin in the new year with a new presenter, who is yet to be confirmed," he said.

Goodier's countdown competes directly with commercial radio's Pepsi Chart Show, hosted by Neil Fox and syndicated to 100 local stations across the UK.

His music company produced Holly Valance's hit

The DJ said: "I've had a great time at Radio 1 but felt that my 15-year anniversary was a good time to move on."

Goodier has previously said that the station was now a "very cool, young station", compared with when he joined, and DJs like Dave Lee Travis and Steve Wright ruled the airwaves.

Goodier has said he would "love" to join Wright on BBC Radio 2.

He also founded production company Wise Buddah, which made Radio 1 shows hosted by Pete Tong, Judge Jules and Trevor Nelson.

Its broadcast arm went into liquidation earlier in 2002, but its music arm has gone on to produce number one hits for Atomic Kitten and Holly Valance.

Goodier has also guided the career of a younger Radio 1 host, Emma B.

It has not been decided whether he will continue to be the voice of the chart run-down on BBC One's Top of the Pops.