A proposal by the UK government to improve rural coverage through ‘national roaming’ has been knocked back by mobile network operators (MNOs) as being unworkable and undesirable, according to the Financial Times (FT).

Under the scheme, reported by the BBC in June, UK customers would be able to switch networks for voice calls if their own wasn’t available. The UK government sees ‘national roaming’ as an important way to combat poor mobile coverage.

(According to a recent report by Ofcom, the UK telecoms regulator, nearly one third of mobile customers experience signal loss at least once a week.)

The national roaming proposal, however, has apparently been given short shrift by the UK’s MNOs. According to FT sources, the timetable – to reach agreement on national roaming plans by the start of next year – is seen as unrealistic.

More damaging for the proposal, according to industry executives, is that it’s extremely difficult to neatly carve up networks in the way the government envisages.  It helps explain, they say, why national roaming has not been deployed elsewhere.

Another potential problem is that national voice roaming might lessen the motivation to invest in network differentiation based on coverage.

According to the FT report, industry executives nonetheless insist they are ready to work with the government to reduce the number of so-called mobile “not-spots”, but it’s not yet clear what that might entail.

In an e-mailed statement to Mobile World Live a spokesman for Three UK – the smallest MNO in the UK – simply said “we support the principle of expanding coverage to address areas less well served and are in discussions with government about the most effective means to deliver that”. The operator said it had already achieved around 98 per cent population coverage.

An O2 spokesperson was equally reluctant to go into detail about possible alternate options: “We continue to work with government and the wider industry to find the most effective ways of improving mobile coverage in rural areas and overcoming some of the existing barriers,” he told Mobile World Live. “Our network currently covers 99 per cent of the UK population for mobile phone calls, and we’ll be investing £1.5 billion over the next three years to extend this further, continuing to deliver a great network experience for our customers.”

Vodafone said they would not comment at this stage, while EE had yet to reply to MWL’s enquiries at the time of writing.

Ed Vaizey, the UK’s digital economy minister – according to FT sources – has written to each MNO asking for different ideas about how mobile voice coverage might be extended in the UK.

The UK government has a £150 million budget to provide mobile coverage in areas where there’s currently no signal as part of its Mobile Infrastructure Project.