The next person to play James Bond will be an unexpected choice, the franchise's outgoing director Sam Mendes has said.

Tom Hiddleston, Aidan Turner, Idris Elba, Damian Lewis and most recently Billy Elliot star Jamie Bell have all been touted as possible 007s.

Speaking at Hay Festival, the British filmmaker said the sole choice for the next star of the hugely successful franchise lies with producer Barbara Broccoli.

"There's this constant debate about who's going to be the next Bond," adding, "The truth is - and here's the headline: it's not a democracy".

"Barbara Broccoli chooses who's going to be the next Bond: end of story.

"I can guarantee whatever happens with it, it will not be what you expect. That's what she's been brilliant at, and that's how it'll survive, " Mendes insisted.

Mendes, who directed Skyfall and Spectre, also confirmed he will not be returning to direct the next film, saying he is ready to work on something new.