Up to 6 billion will be spent on improving road capacity, Transport Secretary Geoff Hoon has announced.
The money will be spent on providing an extra 520 miles of motorway lanes. The increased capacity will be achieved through road widening and opening up sections of the hard shoulder.
Roads that will feature hard-shoulder-running trials include the M1, M3, M4, M6, M25, M62 and .
Hoon also announced plans to spend an additional 250 million to get more ultra-low-carbon vehicles on Britain's roads.