Vodafone Spain has formally asked CNMC, the country’s new regulator, to suspend the network-sharing agreement between Telefonica (Spain’s largest network operator) and Yoigo (the smallest mobile player) on the grounds it restricts competition.

The Spanish unit of Vodafone sees unprecedented close cooperation between the two operators. And because its two rivals now have very similar mobile-fixed offers, competition – says Vodafone – is compromised.

Vodafone’s approach to CNMC follows a complaint on 29 August it made to the now defunct CNC, the country’s anti-trust watchdog.

CNMC combines CNC and CMT, Spain’s telecoms regulator.

Orange’s Spanish unit, on 16 September, also lodged a complaint with CNC over the Telefonica/Yoigo deal after failing to make progress with an earlier complaint to CMT.

It’s not clear if Orange has approached new regulator CNMC, but it has made no secret of its desire to see the network agreement cancelled.

According to an unnamed Orange source, cited by Reuters, the mobile operator believes the tie-up hurts market competition by removing Yoigo as a contender in the market by effectively turning it into an off-shoot of Telefonica. This, says the source, helps Telefonica gain more market share in fixed-line services.

Under the terms of the infrastructure-sharing arrangement, Telefonica can access the LTE network of Yoigo to offer services. Yoigo can also bundle its larger rival’s fixed voice and broadband with its own mobile services.

The two partners have also extended an existing national roaming deal whereby Yoigo has access to Telefonica’s 2G and 3G network.