Steven Moffat has not yet started looking for the new 'Doctor Who' companion.

Jenna Coleman with Steven Moffat

Jenna Coleman with Steven Moffat

Jenna Coleman is to leave her role as TARDIS traveller Clara Oswald during the current series but showrunner Moffat has revealed the search for a new co-star for Twelfth Doctor Peter Capaldi is yet to begin because work on the last episodes hasn't finished yet.

Speaking on the first day of the Doctor Who Festival at London's ExCel Centre on Friday (13.11.15), Moffat said: "We went to the BBC yesterday (12.11.15) to talk about the type of person we might be looking at. To my unending terror, we have not yet finished Episode 11 and Episode 12 is nowhere near finished so we haven't actually delivered the show yet."

Capaldi hasn't yet turned his attention on who his new co-star could be but he's looking forward to getting involved in the decision making process.

The actor said: "I'm not quite sure where we're at but I will (be involved) at some point. Obviously at the end of the day, it has to be someone I'm happy to work with."

Capaldi, Moffat, writer Mark Gatiss, Missy actress Michelle Gomez and Ingrid Oliver - who portrays fan favourite character Osgood - will all be attending the Doctor Who Festival this weekend. And Jenna Coleman will be participating in a Q&A when she appears at the event on Saturday (14.11.15).

Go to www.doctorwhofestival.com for tickets and information.