Nearly two million homes will have their TV signals interrupted as a result of 4G mobile services, the government has predicted.

The government is preparing to auction off spectrum to mobile operators to carry faster 4G services like mobile TV and video conferencing. A large chunk of that spectrum was previously used to carry terrestrial TV before the analogue switch-off.

Due to the close proximity of the spectrum that is being auctioned to the digital TV spectrum now being used, the government, after consulting with regulator Ofcom, says programmes for two million households will be blocked or interrupted.

Culture minister Ed Vaizey said around 945,000 households that use signal amplifiers to boost their television reception could be affected. In addition, another 953,000 homes that rely on communal aerials could suffer.

Ofcom said an estimated nine million homes use TV signal amplifiers, and that there are 5.6 million homes using communal aerial systems. Vaizey said the problem could be largely "mitigated" through the use of reception filters fitted at the homes affected, or having the aerials themselves repositioned.

Ofcom has recommended that mitigation work should be paid for by the mobile operators who win the 4G licences.

A relatively small number of homes however, under 10,000, may be forced to buy satellite or cable TV packages to get any free-to-view channels.

It is "almost inevitable" that the much-delayed 4G auction will be sent back to the drawing board, and held up by more litigation from mobile operators who object to Ofcom’s plans for the joint award of 800Mhz and 2.6Ghz spectrum, analyst Ovum has predicted