A new Doctor Who film finally looks to be on the cards following years of rumour and speculation, and almost 50 years after the Time Lord was last transported to the big screen.

David Yates, the director of the last four Harry Potter films and TV drama State of Play, told US entertainment industry trade magazine Variety that he has started work on a feature film adaptation of the sci-fi drama with BBC Worldwide, the corporation's commercial arm.

But fans of the current Doctor, Matt Smith, could be disappointed, as Yates said that the film would be "quite a radical transformation" from the latest BBC1 series which ended in October.

Yates and the BBC also cautioned that the project remains in the early stages of development, with no script or cast, and will not reach cinemas for several years.

"We're looking at writers now. We're going to spend two to three years to get it right," Yates told Variety. "It needs quite a radical transformation to take it into the bigger arena."

Yates also suggested that the film would not be written by either Russell T Davies, responsible for successfully bringing Doctor Who back to TV in 2005, or Steven Moffat, who replaced him as showrunner and lead writer in 2009.

"Russell T Davies and then Steven Moffat have done their own transformations, which were fantastic, but we have to put that aside and start from scratch," he said.

"We want a British sensibility, but having said that, Steve Kloves wrote the Potter films and captured that British sensibility perfectly, so we are looking at American writers too."

A BBC spokesman said: "A Doctor Who feature film remains in development with BBC Worldwide Productions in Los Angeles.

"The project is unlikely to reach cinemas for several years and as yet there is no script, cast or production crew in place."

Variety magazine reported that Yates is working on the film with Jane Tranter, the Los Angeles-based head of the BBC's Worldwide Productions. Tranter oversaw the show's return to BBC1 in 2005 as the corporation's drama controller.

It is almost 50 years since the last big-screen adaptation of the long running TV drama. Doctor Who and the Daleks made its debut in 1965, with the sequel, Doctor Who: Daleks' Invasion Earth 2150 AD airing a year later. Both 1960s movies starred Peter Cushing as the Doctor.

Doctor Who was dropped by the BBC after 26 years in 1989, returning for a one-off TV movie in 1996, starring Paul McGann.

The TV series returned to BBC1 in 2005 with Christopher Eccleston cast as the Time Lord, before David Tennant took over for the next three series and 2009's specials. Smith has been in the lead role for the past two series.

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