The first interactive British-television campaign begins this month with the launch of a new promotion for Unilever's Chicken Tonight Stir It Up! brand. The campaign began this week on ITV and Channel 4 but at the end of the month subscribers to Sky Digital will be able to interact with the two 30-second advertisements to obtain money-off coupons and recipe suggestions.

The slightly bizarre advertisements show various ways of livening up chicken (hence the headphones!). At the end of the commercials, an icon will appear on screen inviting viewers to click a button on their remote control.

This gives direct access to the company's "Creative Kitchen" website on Sky's open digital television service and from there to coupons and recipes.

There are more than 2.6 million subscribers to Sky Digital in Britain and, according to Ogilvy & Mather in London, which developed the interactive potential of the campaign, the decision to do so was driven by the newly available technology.

"This campaign is not driven by focusing on brand decisions," says Mr Ian Kenny, account director at Ogilvy & Mather. "It is entirely technology driven."

The number of subscribers to the digital service now represents a significant audience for advertisers, which will become increasingly attractive as digital penetration increases.

While general media coverage of the arrival of digital television usually concentrates on the number of television channels that will become available, advertisers have been more aware of the interactivity that digital will offer.

"We will be able to directly measure response to the television advertisement simply by counting the coupon requests and that's invaluable," says Mr Kenny. "Punters are rewarded for watching the advertisement and, by being able to measure the responses, we're closing the loop between advertiser and consumer."

Measurability is a major plus for advertisers but the potential negatives of interactivity are equally obvious. While the consumer is following up on one advertisement that caught their attention, they are missing the advertisement which follows it. To counteract this, the Chicken Tonight advertisement will be the last one in the break so that viewers will not miss another advertisement when they go recipe browsing.

A spokesperson for Sky said that the positioning of Unilever's advertisement was quite deliberate and that, as more and more advertisers produce interactive commercials, the networks and the advertising industry would have to devise guidelines which would protect non-interactive advertisers.

The creative content of the two Chicken Tonight Stir it Up! commercials was devised by J. Walter Thompson in London.