BT may have to wait until the end of the year before it can complete its takeover of EE, the mobile firm's CEO has revealed. Speaking this morning on BBC Radio 4's Today programme, EE chief Olaf Sawntee said the companies hoped to have the £12.5 billion deal passed by the competition authorities by "the end of the year", suggesting many more months of delay before the two can merge.

The Competitions and Markets Authority - the UK's competiton watchdog - began probing the deal last month, asking interested parties to submit their views on the merger. Many are worried about the competition implications of the UK's biggest fixed-line telephone and broadband provider taking over the UK's biggest mobile network.

The mobile phone market is in a massive state of flux, with Three and O2 also merging, reducing the number of major players to only three. There are fears that reduced competition in the market will eventually lead to higher prices for consumers, as well as other damaging effects for the economy. For example, the government is far less likely to earn significant income from the auction of 5G spectrum with only three major bidders.

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Rivals such as Vodafone also fear that BT wil use its dominance of the fixed-line market to harm competition. The mobile networks all buy "backhaul" bandwidth off BT to support their mobile data networks, and rivals worry that they will be charged more for this bandwidth than EE will be, making it harder for them to compete on price.

EE growth

Whilst it waits for the BT deal to be rubber stamped, EE is continuing to add 4G customers at an impressive rate. The company added 1.7m new 4G customers in the first quarter of this year, bringing its total number of subscribers up to 9.3m. Almost half of those signed up for EE's "double-speed" tariffs, which offer download speeds of up to 90Mbits/sec. EE claims its 4G network now covers 87% of the UK population, whilst its double-speed network reaches 67%.

The company is also making surprising gains in fixed-line broadband. It added 50,000 new fixed-line broadband customers in the first quarter, mainly as a result of cross-selling to its mobile customers.

Swantee told the Today programme that he didn't know what would become of the EE brand if the BT takeover is approved. He said that BT would take its time to decide whether to expunge the EE name or continue to use it for its mobile operations.