Martin Freeman has reportedly turned down a lead role in The Hobbit - so he can continue playing Sherlock Holmes' sidekick on TV.

The Love Actually star was approached to appear in the upcoming big-screen adaptation of J.R.R. Tolkien's classic novel but was forced to reject the offer because he is still under contract to play Dr Watson on the BBC's series Sherlock.

A source tells The Sun, "It was one of the most difficult decisions of his career. MGM, who are making the film, only got a formal offer over in the last couple of weeks."

"It was too late for Martin because he had already signed up for another series of Sherlock. It was agonising but he had no other choice."

Director Peter Jackson is said to be searching for an unknown to take the role.

Peter Jackson has been reported being approached to replace Guillermo del Toro to serve behind the lens, the issue has not been confirmed yet. Jackson, meanwhile, is writing the script for the movie along with del Toro, Fran Walsh and Philippa Boyens.

'The Hobbit', which will re-create the scenes of the novel with additional events that make an impact to 'The Lords of the Rings', will be split into two parts. The first part is is expected to arrive in December 2012, while 'The Hobbit 2' will come out a year later. The two films are allegedly planned to be shot back-to-back in New Zealand.

Source: Press Release