The Government is to begin a consultation on raising the speed limit on Britain’s motorways from 70mph to 80mph.
Transport Secretary Philip Hammond said the limit was “out of date” and a higher one would bring economic benefits.
It is understood the consultation will be launched later this year with a view to introducing the new limit in 2013.
Mr Hammond said: “Now it is time to put Britain back in the fast lane of global economies and look again at the motorway speed limit which is nearly 50 years old, and out of date.
“Increasing the motorway speed limit to 80mph would generate economic benefits of hundreds of millions of pounds through shorter journey times. So we will consult later this year on raising the limit to get Britain moving.”
But confirmation of the consultation led to immediate warnings of the possible cost to the environment and increased risks for drivers.
AA president Edmund King welcomed the move: “Eighty miles per hour in a modern car in good weather at a safe distance from the car in front is perfectly safe. Driving at 50mph tailgating the car in front is not.
“Eighty miles per hour is already accepted by most as the de facto limit so it is better to legalise this limit and enforce it. The best speed limits are limits that drivers understand and respect.”
An AA/Populus poll in March 2011 of 12,865 AA members showed that 63 per cent felt the motorway speed limit should be increased, 23 per cent felt any new motorway speed limit should be strictly enforced and 39 per cent felt any new motorway speed limit should be enforced as the 70 limit is now.
But Stephen Joseph, chief executive of Campaign for Better Transport, said: “Increasing the motorway speed limit to 80mph would not help the economy and would increase costs for drivers.
“It would also add to pollution and increase road casualties. Responsible motorists know that driving steadily at or below 70mph is most fuel-efficient, reduces jams and is safer.
“Opinion surveys show that the public will only support increases if they comes with full enforcement, which is not possible in the current economic climate without a massive increase in the number of speed cameras on our motorways.”