Yahoo! has inked a deal to exclusively sell banners and sponsored link inventory on 3 UK's content portal, with the first ads going live later this month.

The operator has already experimented with mobile advertising - its Rhythm New Media-powered ad-funded music video service has 1.4 million registered users.

Yahoo! already manages ad-inventory for Vodafone UK and T-Mobile UK.

3 cites M:Metrics research that says its portal is the second most popular mobile site in the UK behind the Facebook mobile homepage.

It also claims to have the highest percentage of subscribers accessing mobile internet services of any UK operator.