The joint venture, codenamed Project Oscar, was first announced in June last year by Everything Everywhere, Telefonica and Vodafone. Like its US counterpart Isis, the venture aims to create a single mobile wallet platform hosting cards, coupons and transactionsal information on the SIM card. Banks, card schemes, retailers, transit companies and other mobile operators would be able to rent space on the SIM under a subscription model.

Oscar is not alone in arousing the interests of European competition authorities. The Dutch Sixpack collective of banks and telcos have set back their planned launch date until 2013 while they submit their plans to Brussels for approval.

The UK telcos have not helped their case by excluding smaller UK mobile operators such as Three from the early stages of the project. Three in turn has taken its case to Commission and the UK's Office of Fair Trading.

In submitting its plans for inspection, Oscar has raised the spectre of Google, which plans to launch its own mobile initiative on UK shores during the Olympic Games this summer.

"If approved, the joint venture will benefit UK plc as a whole," the partners told the Guardian in a statement. "It will promote competition by bringing together the necessary scale to offer a credible alternative to the established online payments and advertising platforms offered by large US-based internet players."

The EC's competition directorate has 25 days to either agree, demand amendments or extend its investigation.