Lorries and taxis are to be allowed to the use the controversial car share lane on the busy Avon Ring Road.

The stretch of road where solo motorists are banned at certain times of the day will also be shortened.

South Gloucestershire Council introduced what it called the 'Shareway' in 1998 on the A4174 between Bromley Heath and Hambrook - only the second of its kind in the country at the time.

Its aim was to encourage car sharing and cut the number of single occupancy vehicles on the road.

But it was criticised for penalising those who could not share cars and for encouraging motorists to use rat runs in order to avoid the ring road.

Now the hours when the lane - known both as a HOV lane and a 2+ lane - is in operation will be cut so the ban comes into effect 30 minutes later at 7.30am, continuing until 9.30am, encouraging more commuters to stagger their journeys.

Lorries and all taxis will also be able to use it and an experimental extension of the lane from the Church Lane overbridge to the Wick Wick roundabout will be removed.

Brian Allinson, the council's cabinet member for transport, said: "The ring road is suffering from an ever-increasing volume of traffic, so we need to increase its capacity and reduce congestion.

"We have already lengthened the left and right-turn filter lanes at the Hambrook lights but we also need to make radical changes to the operation of the 2+ lane.

"By allowing lorries to use the lane, we will be able to provide a priority route to the M32 junction. This should reduce pollution as HGVs won't be sitting in stationary or slow moving traffic, which is a common feature of the general purpose lane.

"The change should also improve road safety, as HGVs will no longer be forced to suddenly change lanes, which currently causes a hazard for other road users."

Mr Allinson said taking vehicles out of the general purpose lane should cut journey times for drivers who could not car share.

Opening the 2+ lane to all taxis would also allow them to be driven along it without passengers, while lorry drivers would have an incentive to use the ring road instead of other cross-country routes to reach the motorway network.

Mr Allinson said a study into weight limits along some of those routes, including through Codrington, would be carried out to prevent lorries being driven through rural areas.

The changes come after a council review of ways to improve the efficiency and effectiveness of the ring road and the HOV lane.

But it would risk losing Government funding for road improvement schemes if it removed the lane altogether.

It said use of the lane had levelled off in recent years, despite efforts to promote car sharing.

Mr Allinson said: "This does suggest that of those drivers that are left, many of them simply cannot car share for various reasons."

Figures show the HOV lane is currently used by about one in three of all vehicles and of those, a quarter shouldn't be there. It carries the same number of people as the general lane but in fewer cars.

Enforcement is carried out by the police as the council has no powers to deal with moving traffic offences but the authority wants to investigate a more effective regime.