Hugh Jackman took a pay cut to ensure 'Logan' received an R-rating.

Hugh Jackman

Hugh Jackman

The forthcoming superhero movie's director James Manghold has revealed the Hollywood star opted to get a reduced salary to help convince 20th Century Fox to keep the film - the third and final installment of the 'Wolverine' solo trilogy - at the rating.

Tweeting from this year's Butt-Numb-A-Thon film marathon, Aint It Cool News' Eric Vespe wrote: "Mangold said that Hugh Jackman took a salary cut because he wanted to do an R-rated movie."

R-rated films tend to earn less at the box office because only older viewers can buy tickets as the "R" stands for "Restricted", meaning anyone under 17 requires an accompanying parent or adult guardian with them.

Fox's concerns came after 'Deadpool' became the highest grossing R-rated movie of all time and the best grossing 'X-Men' movie.

'Logan' is the 10th motion picture in the 'X-Men' series and is slated for release in March 2017.

Jackman will reprise his role as James "Logan" Howlett/ clawed mutant Wolverine for the eighth and final time in the upcoming movie.

The film is set in 2024, when mutant births are in severe decline for an unknown reason.

A government-type organisation called 'Transigen' are turning mutant youngsters into killing machines.

Logan is said to be depicted as looking bad, drinking a lot and having his powers fading, while he heals more slowly - sometimes not at all.