A new video promoting One Direction's upcoming appearance on X Factor Australia has been posted online.

The British boyband, who were pieced together in 2010 on the British version of the reality TV show, are said to have been lined up as guest mentors on the programme.

The Australian edition of the show, which features the likes of Ronan Keating and Spice Girl Mel B, is due to launch its fourth series on August 20.

A video has been posted on the show's official YouTube page of the One Direction lads attempting to promote their upcoming appearance.

They appear to struggle however to contain their trademark laughs and smiles.