Ofcom's 4G and 5G spectrum auction will feature six approved bidders

Ofcom aims to hold the spectrum auction 'as soon as possible'

Ofcom has given the green light for six operators to bid in its forthcoming 4G and 5G spectrum auction, now that the legal action fromThree UK is out of the way.

BT-owned EE, O2, Three, Vodafone, obviously, are all represented, but they will be joined by Hull-based ISP Connexin and Airspan Spectrum Holdings, a subsidiary of US firm Airspan.

TalkTalk, meanwhile, is notable by its absence following its corporate decision to give-up on mobile.

The auction, which Ofcom hopes to kick off at the end of March, will see 40Mhz of frequency in the 2.3GHz band on offer, which will be immediately available for 4G services; and 150MHz in the 3.5GHz band, which will be used for 5G services.

The auction will also impose a cap of 255MHz on the "immediately usable" spectrum, which means that BT-owned EE will not be able to bid for any spectrum in the 2.3GHz band, as it aleady owns around 43 per cent of all available mobile spectrum.

A cap of 340MHz has also been placed on the overall amount of mobile spectrum a single operator can hold as a result of the auction.

Ofcom says it now plans to hold the auction as "soon as possible", after legal challenges from Three and BT were both thrown out by the Court of Appeals earlier this month.

Three had called for Ofcom to impose a 30 per cent spectrum cap, slamming the watchdog's proposed 37 per cent cap as "meaningless" and bad for competition.

BT-owned EE, on the other hand, accepted Ofcom's 37 per cent cap for 4G services, but launched legal action to stop Ofcom imposing the same cap for the 3.4GHz 5G band.

Philip Marnick, Ofcom's spectrum group director, said: "We're pressing ahead with the auction to make these airwaves available as quickly as possible.

"This will benefit today's mobile users by providing more capacity for mobile broadband use. It will also pave the way for 5G, allowing operators to launch the next generation of mobile technology."