Each brand will have interactive banner adverts on different pages of the Orange World portal from today.
It follows the launch last week of a 拢5m campaign featuring inflatable animals to promote its new tariffs.
The mobile advertising will initially be seen by 20% of customers using the portal, depending on handset capability. Orange intends to use data collected on this trial audience to test what works and plan its future mobile advertising strategy.
Future ads will be targeted at particular user content. Customers who download games on their mobile phones will receive interactive ads for the X-box. New Jaguar models will be promoted on video content, with other advertisers sponsoring free film and music video clips.
Users of location-based services could be targeted with adverts for nearby restaurants or coffee shops.
Research has shown that 89% of major brands will be marketing via mobile by 2008, with the platform tipped to be more powerful than television. Analysts have predicted that mobile advertising spend will reach 拢60m this year, rising to 拢5bn by 2010.
Coca-Cola marketing manager James Eadie said: "As a way of connection, it ought to be phenomenally powerful and more important than TV. So we should be spending 50% of our marketing budget within decades."
Orange, part of the France Telecom group, has 57 million mobile subscribers across 17 countries.
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