Fitting speed-limiting devices in cars could prevent up to 29 per cent of road accidents that result in injuries, according to a report by a government advisory body.
The Commission for Integrated Transport said there would be real benefits from the voluntary introduction of intelligent speed adaptation (ISA), which automatically slows a car down to within the limit for the road on which it is being driven.
Ministers plan to help councils draw up digital maps with details of the legal speed on every road. The speed-limiter devices would then use satellite positioning to cross-reference a vehicle's location with its speed: when the vehicle exceeded the limit, power would be reduced and the brakes applied if necessary. But the campaign group Safe Speed warned against their use, saying they would encourage drivers to enter a "zombie mode".
The report, whose proponents say that 3,000 people are killed on British roads every year, does not recommend the compulsory fitting or usage of speed-limiters, but calls for the Department for Transport to consider how to promote the availability and take-up of the technology.
John Lewis, from the Motorists' Forum, said he believed the devices would help drivers obey limits and therefore keep their licences, "but we believe that the system should be voluntary, and that they decide if they want to over-ride the speed limit".
The president of the Automobile Association, Edmund King, said: "The best speed-limiter is the driver's right foot and we need to educate ourselves to use it appropriately."
The Liberal Democrat transport spokesman Norman Baker added: "This is well meaning but any attempt to control speed could mean that drivers might not be able to accelerate out of dangerous situations. This could make road safety worse."