LONDON, UK: The world's leading Internet companies including Google and Yahoo have signed up to a set of targeted advertising guidelines in Britain to provide consumers with greater privacy and protection.

Targeted or behavioral advertising, where adverts are sent to a consumer based on Internet browsing activity, made headlines in Britain last year when the advertising technology firm Phorm announced partnerships with leading Internet providers.

The Phorm agreements with BT, Virgin Media and Carphone Warehouse prompted some to warn that online privacy would be eroded, a concern that Phorm denies as it says it looks at Web users' anonymous browsing trends.

Internet advertising has grown rapidly in recent years, and brands hope to develop it further by providing consumers with more relevant adverts based on their previous browsing activity.

A Web user going on holiday could be sent adverts for hotels, car hire and restaurants in their desired location, for example.

"Behavioural advertising makes up about 20 percent of the online display advertising market, and if this is going to grow, we need to have consumer trust," Nick Stringer, head of regulatory affairs at the Internet Advertising Bureau, told Reuters in an interview.

The IAB in Britain said it had launched a set of good practice principles after working with key Internet players such as Google, AOL, Microsoft, Phorm and Yahoo, in the last year.

Under the proposals, all online behavioural advertising platforms must clearly inform a consumer before taking any data, they must provide a way for users to decline behavioural advertising and preferably seek a consumer's consent.

They must also provide information, explaining what they do with the data.

The IAB said it had signed up 10 partners, which were advertising networks, technology companies and online publishers.