Spanish telecom Telefonica ended the suspense Tuesday afternoon by confirming that it will sell its British mobile unit, O2, to the Hong Kong-based conglomerate Hutchison Whampoa for $15.3 million.
The announcement follows two months of due diligence performed by the companies after they said in January that they were in exclusive negotiations for O2, which is the U.K.’s second-largest mobile provider. Telefonica (TEF) confirmed the size of the deal on Tuesday, noting in a letter to shareholders that Hutchison Whampoa will initially pay a total of $13.75 billion with an additional deferred payment of about $1.5 billion. The companies plan to close the deal by the end of June 2016.
Hutchison Whampoa — chaired by Li Ka-Shing, Asia’s richest man — already owns ‘3’, a smaller British mobile and broadband provider that will be combined with O2 as a result of the deal to form the U.K.’s largest mobile network with more than 30 million subscribers. The deal is the largest acquisition to date for Li Ka-Shing, who has been investing furiously in overseas assets in recent years.
The deal, which is likely to face heavy scrutiny from European regulators concerned with reduced competition in the industry, is the latest example of consolidation in the U.K.’s telecommunications market. British telecom BT (BT) said last month that it agreed to pay almost $19 billion to acquire U.K. mobile operator EE after previously being rumored as a potential suitor for O2. Meanwhile, British telecom giant Vodafone (VOD) has recently been linked to a potential takeover of Liberty Global.
Fortune noted in January that Telefonica has been looking to sell O2 as part of its plan to shake up its portfolio of holdings while focusing its investment strategy on markets elsewhere in Europe as well as Latin America. In order to purse those investment plans, Telefonica also needs the O2 sale to reduce its massive stockpile of debt, which totals roughly $49 billion.
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