Speaking at the press screening of the Christmas Episode, The Doctor The Widow and The Wardrobe, Moffat confirmed that the duo will rejoin the Doctor in the TARDIS for the next series of the show, but that sometime during the series the couple's story will come to a heartbreaking end.
Moffat teased that he wouldn't say when, and certainly not how, the couple would leave, but that it would happen during the series and then their story would be over.
Matt Smith was asked if he would be sad to see Gillan leave.
Yes, absolutely…and Arthur. We’ve had the most incredible journey and we took over the show and we really had to sort of hold hands and help each other through it in many ways. So, yeah, it’s very disappointing. But, you know, one has to sort of remember that this show is about change and regeneration and that’s what galvanises it and pushes it forward and it’s about looking forward alwaysA new companion, who has yet to be cast, will be joining the Doctor.
The press launch was held in Studio One at Television Centre in London, where many episodes of the classic series of Doctor Who were recorded. It was attended by a specially invited audience, including several MPs including Shadow Chancellor Ed Balls and, reportedly, Chancellor of the Exchequer George Osborne.
For a full report, including an audio clip of the announcement, see Life of Wylie.