AT&T is reportedly looking to extend its exclusive US carrier deal for the iPhone. The company was the first to strike a deal with Apple when it announced in 2007 that it would provide service for the handset through newly-acquired Cingular.

Reports in The Wall Street Journal suggest that AT&T is now seeking to extend the deal to provide exclusive service for the iPhone until 2011.

AT&T has generated major revenues from the millions of iPhones sold in the US. However, the company is also said to be paying handsome subsidisation costs to carry the handset.

The practice of locking the iPhone into a single carrier has long been a point of contention with Apple's customers and carriers.

Consumers in Europe have decried the company's exclusive deals with O2, T-Mobile and Orange. In France, Orange was forced to offer unlocked handsets, while T-Mobile had to go to court to retain its exclusive deal.