"Orange UK and Apple have reached an agreement to bring iPhone 3G and 3GS to Orange UK customers later this year," the network said.
Orange, which claims it has the largest 3G network in the UK, said it will sell the handset in all its shops, as well as through its website, telesales channels and selected high-street partners.
The network has yet to release availability dates or pricing for the handset. However consumers can register their interest at a dedicated website.
O2 has responded with a barbed statement stating its continuing relationship with Apple, but mentioning its deal with the iPhone's rival Palm Pre smartphone.
The two companies hope to complete the deal in October, provided the plan gets approved by competition regulators. Orange and T-Mobile are currently the third and fourth largest operators in the UK, but the combined company would leapfrog O2 and Vodafone to become the UK's largest with 28.4 million customers and a 37 percent share of the market.
If the merger gets the green light, it's expected that the two brands would continue to operate for at least 18 months while the company decides on its future marketing strategy.
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