Aidan Turner is known for his steamy – and often shirtless – portrayal of Poldark in the hit BBC series.

But the frequently bare-chested actor has confessed he is now constantly having to “fight” to keep his top on, as he says show bosses are adding storylines that are not in the original Winston Graham books in order to get him to strip off.

Speaking of the second series of the popular drama, the 33-year-old said: “They were trying to make me take another dip in the sea this time, but it’s not in the books.

Poldark star Aidan Turner (Laura Dale / PA Wire/PA Images)

“It was in the books last time, but this time if it’s not in the books, I have a good fight not to do things.

“And I’m certainly fighting the cause to keep my clothes on for this one,” he told The Mirror.

Aidan’s impeccably toned physique was on display several times during the first season of Poldark, and it proved a real ratings winner for the BBC, so the jury is out on whether a more covered-up Ross Poldark will have an impact on viewing figures this time round.

He has also admitted that having to go shirtless while being in tip-top physical condition is demanding: after all, it takes a lot of work to hone that body.

Poldark returns for series two on Sunday (BBC/PA Images)

Speaking of the training he has to do when preparing to go shirtless, he said: “It’s not that I’m obsessed (with working out), but if I feel it’s right for the character I go for it.”

The handsome star previously criticised the BBC for sending out the now-famous promotional image of him topless in a field holding a scythe.

He said: “I don’t know why the BBC are releasing photos of it. It’s a bit strange. It’s not a stripper show.”

Poldark returns to BBC One on Sunday September 4 at 9pm.