It is expected to be announced today that the speed limit on motorways will rise to 80mph.
As a concession to those concerned about safety, more roads in built-up areas will be reduced to a 20mph limit.
Ministers argue that raising the limit will provide a boost to the economy, saying that shorter journey times will improve productivity at work.
But environmental groups have criticized the decision, saying that the higher speeds mean higher greenhouse gas emissions.
Brake, a bunch of road safety campaigners, called the 80mph move a mistake.
’The government should be looking to reduce the number of deaths and injuries on our road not putting forward proposals which are likely to increase them,’ a spokesperson for the group said.
‘We work closely with families of those who have died in car crashes and for every statistic there are real people who are suffering.’
The plans are set to be confirmed at the Tory party conference next week by Transport Minister Phil Hammond.
He will argue that, as well as being a boost for business, the move will bring the law into line with the reality of what is happening on the roads, with the 40-year-old 70mph limit openly flouted by many drivers.