Drivers should be able to turn left at red lights in a bid to ease congestion, the Conservatives have proposed.
The plan is based on the US where drivers can turn right at red lights
The Tories' economic competitiveness policy group has put forward the idea as part of a 10-point transport plan.
Other schemes include new carriageways and underpasses, removing "dangerous" cycle paths and widening junctions and lanes around large roundabouts.
The Tories stress the proposals by the group, one of several set up by leader David Cameron, are not party policy.
The traffic light idea is based on practice in some states in the US where motorists are allowed to turn right at red signals.
The group also suggests rephasing traffic lights to give priority to main roads, putting cycle lanes on pavements where there is room, letting taxis and motorbikes use bus lanes, providing more pedestrian footbridges and underpasses, and reviewing speed limits.
The proposals are the party's "interim thinking" on how transport could be improved.
Chairman of the policy group, John Redwood, will unveil the suggestions on a visit to Barnet in north London on Friday.
He told the BBC's Today programme the proposals would increase capacity on roads by 10%, while freer flowing traffic would cut pollution.
The most important thing to be addressed was road junctions, as they were where most accidents occurred and were major causes of congestion, he continued.
He denied the proposals ignored pedestrians and cyclists.
"We are saying that cyclists and pedestrians are very important and we want them to have better provision than they have at the moment," he said.
"What we are doing is greener, cleaner and safer."
But Andrew Evans, professor of Transport Risk Management at Imperial College, said he had reservations about the ideas.
"I would expect that the system as a whole would be somewhat less safe for pedestrians and cyclists," he said.
"But I think more generally it would make the environment for pedestrians a lot less friendly than it is now, and that's not what we wish to encourage.
"We wish to encourage more pedestrian activity, particularly for short journeys, rather than cars."