Plans for the first car-share lane on the M1 have been dropped in favour of other forms of traffic management.
The car-share lane would have run from junctions 7 to 10
A car-share lane had been planned from junction 7 for St Albans, Hertfordshire to junction 10 for Luton, Bedfordshire.
The Department for Transport has now decided it is "not the right solution". A spokesman said new technology would be used to manage traffic flow instead.
But the Campaign for Better Transport criticised the move saying similar lanes had worked elsewhere.
The Department for Transport spokesman said: "Car share lanes remain an important part of our congestion-tackling toolkit and we will continue to consider them for use across the network.
"Transport Secretary Ruth Kelly has opened a car share lane on the M606/M62 near Bradford.
"We have also identified around 500 miles of motorway as potential priority sites for new traffic management measures, which may also include more car share lanes.
"The M1 from junction 7 to 10 will now be equipped with controlled motorway technology, similar to that in operation on M25, to maximise traffic flows and improve safety."
The Campaign for Better Transport has accused officials of "burying" the decision not to open a similar lane for the M1 in a report published earlier this month.
Solo drivers would have been banned from the High Occupancy Vehicle (HOV) lane - during rush hour.
The former Transport Secretary promised the car share lane in 2004
The Campaign for Better Transport wrote to Transport Minister Tom Harris in October 2007 asking him to recommit to the M1 HOV lane, but did not receive a reply.
The decision to drop the promised M1 car-share lane was stated on page 65 of an 80-page report published this month.
Rebecca Lush Blum, Campaign for Better Transport's roads and climate campaigner, said: "We are disappointed that the government has decided not to back the important M1 car-share lane.
"Car-share lanes work elsewhere in the world, cutting congestion and carbon emissions."