Hugh Bonneville believes that Downton Abbey creator Julian Fellowes will know when it is time to "put it to bed".

The 51-year-old actor, who plays Lord Grantham in the popular period drama, said, "It's a unique show, in that it feels so big in scale, but it comes down to one person's imagination; [writer and producer] Julian Fellowes.

"It's really him, and he'll know when it's time to tie-up all the loose ends and put it to bed. Shows like Downton are once in a career, and I know it will come to an end eventually - and I can just retire and do some knitting."

Bonneville further told PA that he feels lucky to be part of the show, adding, "I feel like a very lucky actor to be in a show that people love and continues to grow around the world.

"It's something I love doing, and the people involved are a fantastic team. I said to our producer not so long ago, that it's extraordinary to think that five years on, we're not punching each other!"