The government is to open up more motorway hard shoulders to drivers during congested periods after a successful trial in the Midlands under a package of proposals announced on Wednesday.

Parts of the M3 and M4 approaches to London, the M4 and M5 around Bristol and the M3 and M27 near Southampton, which were previously earmarked for widening, will be considered for hard-shoulder use.

The move was part of a six-year, six billion pounds package announced by Transport Secretary Ruth Kelly, which also proposed more tolled lanes, car sharing, urban congestion charging and road widening.

"I am determined to get the best from our road network so that motorists have reliable journey times on roads that are safe and well-managed," Kelly said in a statement.

"The greatest barrier to this is congestion. It is frustrating and has serious consequences for the economy and the environment."

Trials on the M42 in the West Midlands last year showed northbound times fell by more than a quarter and by nine percent heading south when the hard shoulder was opened up to traffic at speeds of 50 mph.

The RAC motoring organisation said if the scheme was to be extended to other parts of the country, the same level of technology and monitoring would have to be put in place.

"It should not be used as a quick and dirty measure, but should be used with other measures as well," RAC spokesman Jon Day said.

Safety campaigners in the past have expressed fears that lives will be endangered because traffic will block emergency services and leave drivers with nowhere to stop if they break down.

The Transport Secretary said the government would look at successful examples of hard-should use in Europe.

She also said it will look at dedicated or tolled lane use in America.

Other measures included giving Leeds, Cambridgeshire and Reading up to 200 million pounds a year for improved public transport and local congestion charging.

"The majority of congestion is in our towns and cities, where the answer cannot be building new roads," Kelly said.

"That is why I will continue to support councils who want to investigate whether radical packages, which include public transport improvements combined with local congestion charging, would be the right solution for them."

The first six million pound instalment from a 60 million pound congestion-easing fund would be available for Bristol, Greater Manchester, Leicester, London, Merseyside, South Yorkshire, Tyne and Wear and the West Midlands to help tackle the problem.