4G auction faces National Audit Office probe after falling more than £1bn short

The UK's National Audit Office (NAO) is set to probe Ofcom's recent 4G spectrum auction, after the bandwidth sale fell short of expectations by more than £1 billion.

Concluded in February, the auction saw telecom giants O2, Vodafone, EE, Three, and BT splash out a total of £2.34 billion for space on the 800MHz and 2.6GHz LTE bands. But the sizeable cash haul was well short of the £3.5 billion estimate offered up pre-auction by the government's Office for Budget Responsibility.

The NAO has confirmed to multiple sources that it intends to launch an investigation into the matter, with The Guardian indicating that the probe can be traced to complaints made by Labour MP Helen Goodman, the shadow minister for media and communications.

"By not making maximising the auction's revenues an objective for Ofcom, the government has failed to get value for money on this project," Goodman is understood to have told auditor general Amyas Morse.

Goodman has since said that she welcomes the NAO's intervention - and seemed to relish the opportunity to indulge in some political point scoring.

"It is entirely right that the National Audit Office has launched this investigation. Serious questions must be answered as to why the Conservative-led government ended up £1bn short of the estimate George Osborne had provided just months earlier," she said.

"When the 3G auction took place, Labour ensured that maximising revenue was an objective. The Conservative-led government did not do the same for the 4G auction, which I believe was a serious mistake," Ms Goodman added.

For its part, Ofcom has sought to distance itself from accusations of failure, commenting that it regarded the 4G auction as a success that had achieved the stated aim.

"The 4G auction was a success, which will deliver the maximum benefit to UK citizens and consumers – in line with Ofcom's statutory duties. It will create competition, with five companies able to launch competitive 4G services," the regulator said in a statement.

"The auction was designed to promote competition and ensure coverage, rather than to raise money. These benefits will deliver significantly more value in the long term to the UK than simply the revenue raised in the auction," it added.