Sir Derek Jacobi has confirmed he is to play a guest role in the third series of Doctor Who, according to BBCi.

The 68-year-old has previously appeared in an online version of the series as "renegade timelord" The Master, but there has been no confirmation of the exact part he will play.

Nevertheless, the Daily Mirror says Jacobi will play a good man who "plays a key role in preventing the world from ending".