Fears over road safety have led to the Government reportedly scrapping a flagship scheme to have a car-sharing lane on the M1.
The lane would have occupied the outside of the M1 between St Albans and Luton and been the first in Britain.
The motorway is being resurfaced and widened from three lanes to four each way to make room for the HOV lane and improve flow.
Due to open in December, the showpiece scheme was to encourage car sharing and let multiple-occupancy cars speed past slower ones.
But it has now been quietly scrapped as being impractical and dangerous by the government's own advisers.
A study has warned it would make motorists crash as they swerved around slow-moving drivers on the road ahead. It also said the scheme was virtually impossible to police.