France could destroy television viewing for thousands of Britons by beaming high-powered digital signals across the Channel, the National Audit Office has warned.

Britain would have to take action to defend the south coast from French signal interference, the NAO said, in a critical report into the Government’s plans to achieve digital switchover.

Analogue signals will be switched off region by region, with the whole country converted to digital television by 2012, according to the Government plan. But if France switches to digital signals before Britain, some English viewers could suffer.

The NAO said: “On current timetables there is a risk that once France has achieved digital switchover, at present scheduled for November 2011, there may be interference with the current digital terrestrial signal in parts of southern England as a consequence of high-powered digital transmissions from France.”

When the southern regions convert from analogue to the stronger digital signal they should be unaffected by French transmissions. Ofcom is holding urgent negotiations with French regulators to coordinate switchover programmes and minimise the risk.

The NAO said: “Any decision to bring forward the [UK] digital switchover timetable, for example to avoid such signal degradation, would result in some additional costs for the BBC.”

The BBC must set aside £800 million from the new licence fee settlement to cover the costs of switchover, including help for vulnerable groups, such as the elderly and disabled.

The cost of switchover is one reason why the BBC has been forced to cut 2,500 jobs and has pledged to make fewer programmes. The corporation would seek compensation from the Government if it was required to pay extra to combat French interference.

Last night Whitehaven was due to become the first town in Britain to switch off its analogue signal. But with hours to go until the 2am deadline, Digital UK, the body overseeing the switchover, estimated that 500 homes in the area had yet to convert their equipment for digital transmission.

Viewers could face blank screens when analogue television is switched off, the NAO warned. Government delays put the switchover timetable in jeopardy and led to a “Red Status Alert” being issued in August before the first phase began in Cumbria.

The NAO reported: “The BBC Trust has not yet set performance indicators to measure the value for money of the operation of the help scheme.

“Initial take-up of the scheme has“ been lower than expected but, without a full understanding of why, there remains a risk that some eligible people who seek help may be left without television after switchover.”

Sir John Bourn, the Comptroller and Auditor General, said: “The BBC will play a central role in the switchover from analogue to digital television. [It] must be on top of its game to get value from the £800 million they have to spend on providing the help scheme.”

The BBC Trust said it accepted the NAO’s findings and would commission a review to monitor the value for money of the help scheme to the licence fee payer.

Jeremy Hunt, the Shadow Culture secretary, said: “Bad planning and delays by Government has meant that there will be no time to learn lessons from the pilot help scheme. The result could be thousands of vulnerable people without television.”

Do not adjust your set

Plus Belle la Vie: a nightly soap opera set in Marseilles, this is the Gallic equivalent of EastEnders. Murders and adultery are the threads which run through the plot. France 3

Star Academy: a reality TV show to find the young musical talent of the year. TF1 channel

Ça se discute: a weekly discussion programme on French social trends. Debates are lively and a recent one ended in a fist-fight in front of the cameras. France 2

Julie Lescaut: France’s best loved detective series where the heroine fights and defeats crime on the streets of Paris. TF1

Le Journal de 20 heures: the 8pm news on TF1 is an institution in France as is its presenter Patrick Poivre d’Arvor, or PPDA as he is known. TF1

Le Plus Grand Cabaret du Monde: the Saturday programme that is a tribute to la France profonde – rural France – with a presenter who makes Terry Wogan seem like the height of urban chic. France 2

Source: Times Database

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