Aidan Turner has hinted the fifth series of 'Poldark' will be the last.

Aidan Turner

Aidan Turner

The 34-year-old actor plays the titular role in the hit BBC1 period drama and, despite already having the green-light for series four, Aidan claims they will have "run out of things" to do after the fifth instalment has come to an end.

Speaking to WWD, the actor said: "I think we run out of things to do after series five, I think that would be our last one. Four was green-lit, five hasn't been yet, and it wouldn't be fair to me to green light it, but it's probably looking like it may happen."

The third series of the hit show is set to air this weekend and viewers are expecting to see an end to the love triangle involving Ross, his wife Demelza (played by Eleanor Tomlinson) and Hugh Armitage (Josh Whitehouse).

Aidan shot to fame on the show and since has been offered roles in big Hollywood movies including playing one of the dwarfs in the hit 'Hobbit' trilogy.

A source told the Sun: "Aidan and Eleanor have become huge stars on 'Poldark'.

"They are getting more and more big offers including Hollywood roles.

"In many ways they're now bigger than the show. Pinning them down to any more is likely to be tricky, not to mention costly - and bosses only have the option to extend his current contract until series five."

Recently, Eleanor, 25, admitted she thinks the cast would feel "very lucky and honoured" to film more episodes of the show.

Speaking in June about the television adaptation of Winston Graham's saga, the flame-haired beauty said: "If we go to five series that would be a dream. We would be very lucky and honoured to get that far.

"I think if we go to five series then that would be a dream come true -- and how many series have done that?"