Apple’s iPhone strategy was dealt a fresh blow yesterday when its exclusive mobile network partner in Germany was forced to make the device available on rival networks.

T-Mobile said that it would make the phone accessible to other mobile operators after a legal challenge by Vodafone claimed that the exclusive deal – under which customers had to sign up to a 24-month T-Mobile contract – breached local competition laws.

A spokesman for the German operator emphasised that the “unlocking” of the handset was a temporary move ahead of a full court hearing in Hamburg in two weeks. Buyers of the “unlocked” version of the phone will also have to pay a hefty premium: it will cost €999 (£718), rather than the €399 for one tied to a T-Mobile contract.

“T-Mobile remains the exclusive provider of Apple iPhones,” a spokesman said. He added that several functions would work only on the handset sold under contract to T-Mobile.

The decision marks the latest in a series of blows for the iPhone. In an attempt to maximise revenues from the gadget – a combined iPod music player, internet surfer and mobile phone – the Californian group negotiated exclusive market-by-market deals across Europe.

In return for exclusivity, the chosen mobile operator had to hand over up to 30 per cent of continuing subscriber revenues to Apple. It is unclear how that model can proceed in Germany now that the phone has been opened up. The model has also been blown apart in France, where local laws have forced Orange – Apple’s chosen French network partner – to open the phone to rival networks when it goes on sale at the end of the month. Britain is now the only European market where the deal remains exclusive to one partner, O2. Apple declined to comment.

Ben Wood, an analyst at CCS Insight, the telecoms research group, said that the Vodafone action had been a “tactical move designed to disrupt sales of the gadget at a critical point in its sales cycle”. A spokesman for Vodafone said that the group was “surprised” by the €600 penalty for the unlocked version of the gadget.

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