The mobile network space in Britain is about to drastically change, with four of the major networks soon going down to three.

Telefonica has announced it will sell O2 to Hutchison Whampoa, which also owns Three UK, for £10.25 billion. The deal means Hutchison Whampoa will eventually have the largest subscriber base in the UK, but it does not come as much of a surprise, considering the deal was rumoured and the pair entered exclusive negotiations a few months ago.

Everything has just been finalised though, and is pending approval by regulators. The UK should therefore be left with Vodafone, EE, and a merged Three UK and O2, though Hutchison Whampoa hasn't confirmed whether it'll maintain O2's brand and services or combine them with Three UK.

Keep in mind Hong Kong tycoon Li Ka-shing, Hutchison Whampoa's chairman, recently bought Telefonica's Irish biz for £650 million and combined it with Three Ireland. He also picked up UK’s Eversholt Rail Group for £1.1 billion.

Telefonica hasn't said much else - apart from it is confident customers will now "benefit from greater value, quality and innovation," and that "new and exciting opportunities" should open up for employees of both businesses.

Regulatory approvals might take up to a year.

READ: Three to buy Telefónica's O2 in £10.25 billion deal

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