Screen stars Sir Ian McKellen and Olivia Newton-John are among the celebrities who have donated signed items to help raise money for the protection of rainforests.

The Hobbit actor and the Grease star have handed one-off autographed items to organisers of The 12 Days of Christmas, an online auction benefiting The Rainforest Foundation Uk.

Other lots in the sale include a guitar signed by rocker Sting and a box set of vinyl records from British band Blur.

The auction, on, will begin on 13 November (12).