Hutchison Whampoa (0013.HK), owner of Britain's fourth-largest mobile operator Three, is in talks with Telefonica (TEF.MC) about buying its O2 network, the Sunday Times reported, citing unnamed city sources.

The price could be as high as 9 billion pounds ($13.63 billion), though discussions are at an early stage and there is no certainty a deal will be reached, the paper said.

O2, acquired by Spain's Telefonica in early 2006, is second in the British mobile market with about 22 million subscribers.

Reuters reported in November that Hutchison was working with an advisory boutique on a deal for either O2 or rival network EE, which is owned by Orange (ORAN.PA) and Deutsche Telekom (DTEGn.DE).

Former state telecoms provider BT (BT.L) has since entered exclusive talks to buy EE.

Neither Telefonica nor Hutchison were immediately available to comment on Sunday.