George Clooney to make Downton Abbey cameo ….sort of.

George Clooney will appear with the cast of Downton Abbey, as an American guest at a wedding -but it’s not expected to comprise part of the series.

Clooney, who is a big fan of the show, has already filmed the scenes, reportedly alongside Hugh Bonneville and Michelle Dockery for ITV’s Text Santa charity fundraiser.

An ITV spokesperson told Guardian Clooney would appear in a sketch, but would not act in the full episode.

Sources told the Sun: “All the plans have been shrouded in secrecy because George was determined for his role not to leak out.

“All the other cast members and crew were also sworn to secrecy. It’s amazing it’s taken four months for someone to find out. This is the biggest moment in Downton history and shows it’s now the biggest drama in the world.”

Seven is expected to air the new season early in 2015.