BT's £12.5 billion takeover of EE is not expected to complete until March next year after the telecoms giant asked the competition regulator to take its probe into the deal to a second, in-depth phase.

The telecoms giant argues that the deal will not reduce competition in the fixed and mobile market and has asked the Competition and Markets Authority (CMA) to fast-track directly to a phase 2 investigation "to consider any complex issues in depth without delay". Earlier this month, BT boss Gavin Patterson had suggested a phase 1 decision might still be possible, which could have seen completion of the deal by September. The CMA expects to say within three weeks whether it will go to a fast-track procedure.