Last week, the media regulator announced that Everything Everywhere, which owns T-Mobile and Orange, would be able to use its existing 1800Mhz spectrum to run LTE (next generation mobile broadband) services, while Vodafone and O2 would have to wait for the delayed auction of the 800Mhz spectrum to take place.
This means Everything Everywhere customers would benefit from faster mobile broadband as early as October this year, which could be up to 18 months ahead of rivals.
Laurence said: "The regulator has always stressed that competition is in the best interests of consumers and the British economy, yet here it is all but agreeing to grant the largest player in the market a headstart on the next generation of mobile internet services.
"This decision leaves Everything Everywhere free to prevent anyone else from launching 4G services, by bogging next year's auction down in endless litigation.
Ofcom said it considered whether allowing Everything Everywhere to use this spectrum in this way would distort competition, and provisionally concluded that it would not.
The regulator said: "Given the benefits this would bring to consumers, Ofcom is minded to allow this change of use."
The decision is due to regulatory approval and the deadline for consultation is on 17 April.
Everything Everywhere had not responded to a request for comment at the time of publication.
O2 did not respond to requests for comment on this occasion, but in the past it has criticised Ofcom over its 4G auction plans.
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