Stellan Skarsgard had no problem going nude in 'Thor: The Dark World'.

The 62-year-old actor has revealed he was comfortable baring all in the sequel to the hit 2011 film, in which he reprises his role as scientist Erik Selvig.

Speaking to BANG Showbiz at the film's world premiere in London's Leicester Square on Tuesday (22.10.13), he said: ''If you've seen what I've done before you'll know that I'm naked in half of my films so it wasn't a big deal. And I was born naked, also! I got a question through my agent asking would I mind [getting naked] and I didn't mind.''

Meanwhile, franchise newcomer Christopher Eccleston, who plays villain Malekith, says he didn't feel pressure following in the footsteps of 'Thor' and 'The Avengers' nemesis Loki, played by Tom Hiddleston.

He explained: ''It wasn't daunting. It was a pleasure. This film has got probably three villains - myself, Tom and Adewale [Akinnuoye-Agbaje], who plays Algrim/Kurse. My threat is very separate. Tom is the threat within the family and I'm the threat from outside.''

While the movie embraces humour, Eccleston's character remains stoic throughout, but the actor admits he was often tempted to crack a smile.

He added: ''It all ended up on the cutting room. They said, 'Continue to be mean, Eccleston. We want a naughty elf.' ''

'Thor' leading man Chris Hemsworth led the red carpet arrivals at the film's premiere and he was joined by co-stars Natalie Portman, Idris Elba, Kat Dennings and director Alan Taylor.