Wills and Harry in Star Wars slap Benicio del Toro’s bum

It promises to be the cheekiest cameo in Hollywood history.

We can reveal that the scene that Princes William and Harry secretly shot when they visited the set of the new Star Wars movie features one of them slapping star Benicio del Toro on the backside.

But as they were both dressed as Stormtroopers, with their faces covered by helmets, there’s no telling which of them did it.

The Royal siblings will have to wait until they attend the European premiere of The Last Jedi this week to see if their secretly shot scene makes the final cut.

The Mail on Sunday revealed the pair have secretly filmed their Stormtrooper roles 

Last year, The Mail on Sunday revealed the Royal duo filmed incognito when they visited Pinewood Studios. And last night a source told this newspaper that their scene involved del Toro’s shady character DJ and rebels Rey and Finn, played by British actors Daisy Ridley and John Boyega, infiltrating a secret base.

Prince William smiles at BB-8 droid during a tour of the Star Wars sets at Pinewood studios. The Duke of Cambridge and Prince Harry filmed their role incognito on the visit

Prince Harry and Prince William, Duke of Cambridge try out light sabers during their visit

As a group of Stormtroopers guard Finn and DJ, ‘one of them, either William or Harry, slaps Benicio’s bottom’, the source said.

‘The new film is packed with laughs and that scripted scene was supposed to bring the house down. But no one knows if that scene made the final cut.’

The Palace refused to comment on the original report, but recently Boyega confirmed the cameo, saying: ‘It wasn’t intimidating, it was fun. I thought, “Of course, it’s Star Wars, they’re going to bring the Royal Family.” It felt fun.’

The premiere takes place at London’s Royal Albert Hall on Tuesday in front of an audience including 400 military veterans and survivors of the Grenfell Tower tragedy.

After the screening, the Princes will host a party at nearby Kensington Palace.