Suits you: George Clooney and Hugh Bonneville pose together in matching grey suits on the set of Downton Abbey

George Clooney has been pictured for the first time on the set of Downton Abbey.

The Hollywood star - who is set to appear in the Text Santa charity special - can be seen holding a clapperboard with Hugh Bonneville as the pair pose in matching grey suits for a picture inside Highclere Castle, Hampshire.

Bonneville, who plays Lord Crawley in the period drama, is said to be close to the A-lister after the pair starred alongside one another in World War Two film, The Monuments Men.

Clooney, 53 – who recently married Human Rights lawyer Amal Alamuddin – is set to play an American wedding guest at the Crawley household.

Although news of his guest appearance was announced in September, Laura Carmichael, who plays Lady Edith Crawley, said Clooney’s appearance on set was a well kept secret with cast members left guessing as to whether it “would actually happen”.

She said: "It was amazing. We didn't know if it would actually happen until he turned up.

"We were filming and then heard, 'He's here! He's here! He's arrived!'"

The 28-year-old also revealed that Maggie Smith’s character, Dowager Countess of Grantham, goes weak at the knees on receiving a kiss from the Hollywood heartthrob.

She said: "There is a very brilliant moment with Maggie and George - and I don't know if I want to give away any more than that really - but Maggie does a very comedy fall," she divulged.

"George plants a kiss and Maggie ends up on the floor, it's wonderful. He was hilarious."