The business, which is held by Carat, is being reviewed via the Walt Disney procurement department. It covers Disney-branded films, such as 0, as well as the Buena Vista music and film distribution business and the Disney TV channels.
The £17 million UK account, which includes media buying for properties including High School Musical, moved into Carat from Vizeum as part of a wider consolidation process in 2005. The agency already handled the majority of the pan-European business.
A Disney spokeswoman said: "Walt Disney Studios has launched a review of its European media agency support, as it continues to roll out a standard 'best practice', procurement-led process across all of its business units. This follows a similar process being undertaken in other marketing agency sectors."