John Hurt has revealed he agreed to appear in David Yates' new Tarzan movie to help the director get the green light from the studio.

The Harry Potter director is making a big budget reboot of the Tarzan story for Warner Bros, starring Alexander Skarsgard as the king of the jungle.

The project fell into some difficulty last year when production was halted, due to budgetary concerns, according to Deadline.

But the film - which sees a Tarzan who has adjusted to civilisation in London returning to his roots - has swung back into action with John among its all-star cast.

The 74-year-old actor revealed: "I've finished working on that. He's always wonderful to work with, very easy is David.

"I don't do a great deal in it - but it was sort of part and parcel of getting the film green-lit."

Tarzan, due out in cinemas in July 2016, also stars Margot Robbie as Jane, Samuel L Jackson, Christoph Waltz and Djimon Hounsou.