It has been revealed that 'Doctor Who' star David Tennant will return for a third series as the time traveller.

Tennant and co-star Billie Piper (Rose) were launching the second series in Cardiff yesterday when Piper told reporters that she would return for a third series.

Speaking about his contract, Tennant said: "Mine's not as simple as that."

But a spokesperson for the show's makers BBC Wales later told the Press Association that Tennant was committed to the programme for a third series in 2007.

The new 13-episode second series of 'Doctor Who' begins on BBC One in April.