Announcement expected to be made on Friday.
Pop band Girls Aloud are rumoured to be the stars of a Christmas ad campaign for jewellery brand Pandora, according to a report in magazine Marketing Week.
It is believed that Pandora retailers were informed of an upcoming partnership two weeks ago but were made to sign a non-disclosure agreement that prevented them from talking about it.
Marketing Week has reported that Pandora is expected to make full details of the Girls Aloud partnership available on Friday.
Girls Aloud are set to release their first single since 2009 on Friday, a track called Something New. The band is also reported to be planning a comeback tour and a greatest hits album.