asked the Secretary of State for the Environment whether he is satisfied that there is adequate examination of improving existing roads when consideration is being given to constructing new roads in Green Belts.

Yes. When considering solutions to traffic problems, the possibility of improving the existing road is the first course to be examined. But where traffic volumes are high and the widening of the existing road would involve destruction of a large number of properties and interference with many others, an entirely new road may be preferable on both economic and environmental grounds.