Multiple sources are reporting that that T-Mobile UK is in talks with Apple to bring the iPhone 3G – last year’s model – to its mobile service, taking away the phone’s exclusivity from competing carrier O2.

Reports from Register Hardware and guardian.co.uk suggest the appearance of the iPhone 3G on the British T-Mobile network could happen in the next few months.

The Register said O2’s exclusive agreement for the iPhone 3GS appears to remain secure. O2 would also carry the iPhone 3G.

“This represents a major shift in how Apple markets the iPhone,” The Register said, “which currently relies on network exclusives to get a decent subsidy; giving that up shows either greater confidence or reflected disappointment in how O2 has priced up the latest offering.”

The report from guardian.co.uk goes a step further: It states it is “understood” that both Orange and Vodafone are interested in providing the iPhone on their networks as well, if Apple changes its strategy. If that were to come to pass, all of the UK’s major cell phone carriers would provide some version of the iPhone.

Richard Moat, T-Mobile UK’s new managing director, has taken his position as the company is in the midst of financial trouble. Because T-Mobile does not offer the best handset selection, gaining access to the iPhone 3G would be a major coup for Moat, and a boon for choice in the UK.