Automatic speed control devices should be installed in cars to force motorists to stick to speed limits, an influential pressure group recommended today.

The Commission for Integrated Transport (CfIT), a government transport advisory group, said that up to 29 per cent of injury accidents on the road could be prevented by the voluntary introduction of intelligent speed adaption (ISA).

The system, which the report recommended drivers installing on a voluntary and not compulsory basis, would automatically slow a car down to within the limit for the individual road on which it is being driven.

However opponents of the report, co-written by the pressure-group Motorists Forum, claimed the idea was dangerous as drivers would enter "zombie" mode, where they fail to pay proper attention to road conditions.

The report, which also looked at the impacts on fuel consumption, emissions, noise and road network efficiency, concluded that, on 70mph roads, adherence to the speed limit could also lead to savings of up to six per cent in CO2 emissions as well as reduce accidents.

It called for the Department for Transport to work with the relevant authorities, organisations and vehicle manufacturers to consider what steps should be taken to support and encourage the future availability of the technology and to promote its take-up.

“This important report shows the very real benefits to motorists from the introduction and use of an ISA system - not just in road safety but also in terms of fuel and money saved," CfIT vice-chairman David Leeder said.

Sir Trevor Chinn, chairman of the Motorists’ Forum, said: “The UK has an enviable record on road safety but we still kill nearly 3,000 people on our roads each year.

“This report shows the potential substantial savings in injury accidents that could be achieved through the introduction of ISA.

“The fact that the report is backed by our members, who represent interests across the motoring spectrum, is testimony to the desire of the motoring world to work with government to make our roads even safer.”

However, the proposals were immediately criticised today, with some saying the devices would potentially numb drivers' reactions to road conditions.

Claire Armstrong, from the road safety charity Safe Speed, told the BBC that the device would be "highly dangerous" for driver reactions. "You've taken the responsibility away from the driver," she said.

Derek Charters, from the Motor Industry Research Association, added: "The last thing you need is one car to be overtaking and then pull back in, in front of the cars in front, because that braking event will then cause everybody to start to slow down, which will then compress the traffic, which then causes an incident."