Mark Hamill will trade 'Star Wars' secrets for information about 'Frozen 2'.

The 65-year-old actor - who plays Luke Skywalker in the science fiction franchise - has been sworn to secrecy about the details of 'Star Wars: The Last Jedi', the latest instalment in the film series but quipped he would be willing to give out spoilers if he could find out how the sequel to animated movie 'Frozen' was going.

He wrote on Twitter: ''In negotiations to exchange Episode VIII: The Last Jedi spoilers for Frozen Two leaks. And no - Knowing Olaf is in the film is not good enough #WaitForVIII #WontLetItGo @joshgad @riancjohnson (sic)''

Mark made his return to the 'Star Wars' franchise for the 2015 movie 'Star Wars: The Force Awakens' and likened it at the time to finding a ''$20 dollar note in old trousers''.

He said: ''Returning to the trilogy reminded me of taking out a pair of old trousers from the back of the closet and discovering a $20 dollar bill in the pocket. It's still as strange for me to talk about being in another 'Star Wars' movie.

''I'm proud of the legacy we left and I'm happy new generations of fans will get to see me and Harrison and Carrie back in the roles people loved. I wouldn't have done this unless Harrison and Carrie were involved. It should be all of us or none of us.''

Meanwhile, director Rian Johnson previously teased that 'Star Wars: Episode VIII' - now known as 'The Last Jedi' - would focus on Rey learning and beginning to understand her connection to The Force.

He explained: ''Part of what's she's dealing with is the realisation that she has this power and this gift. She's taking her first step to coming to terms with this thing inside her that she never knew was there and is just starting to reveal its potential. I don't want to skip ahead two years. I want to see the very next moment of what happens.''