Sky is to offer advertisers the ability to show extended advertising content to viewers who push the green button to access it. Some of the "green button" content can be saved onto Sky+ and HD receiver for later viewing.

Many channels currently use the green button is already used during some trails to allow viewers to book programme reminders. The BBC and C4 have also started to use this service.

It is expected that the Green button content could include extended edits of existing ads; a "behind the scenes" documentary showing how an ad was made; access to exclusive content; an mini-sodes of content related to an ad storyline.

The first campaigns to take advantage of the new functionality will be for Harry Potter and the Half Blood Prince, McMillan Cancer Support, T-Mobile and Ice Age 3.