The A30 between Chiverton Cross and Carland Cross will finally become a dual carriageway as part of the, "the biggest, boldest and most far-reaching roads programme for decades", announced by the Government.

The A30 between Temple and Higher Carblake will also become a dual carriageway, with the cost of both schemes costing an estimated £180 million, while the A303 close to the famous stones at Stonehenge will be put into a tunnel, easing conditions at the notorious bottleneck.

But Labour accused Prime Minister David Cameron of having "a record on infrastructure that is one of all talk and no delivery" while the RAC Foundation warned that the road network would have to cope with an expected seven million more drivers within 20 years.

It has been pointed out that many of the 80 new English road schemes announced today in a £15 billion package are in key coalition constituencies but Deputy Prime Minister Nick Clegg said: "You don't make decisions like this based on a political map."

Mr Clegg was at Stonehenge, where the Government has announced that the A303 close to the famous stones will be put into a tunnel, thus easing conditions at a notorious bottleneck.

Transport Secretary Patrick McLoughlin said it was "the biggest, boldest and most far-reaching roads programme for decades", while Chancellor George Osborne said it would "transform some of the country's most important strategic routes" .

Chief Secretary to the Treasury and chairman of the Cabinet infrastructure committee Danny Alexander said the projects would "help unleash the economic potential of both the regions they serve and of the overall economy".

But shadow transport secretary Michael Dugher said: "The Government has 'announced' plans for road investment at least three times since 2013.

"We know David Cameron's record on infrastructure is one of all talk and no delivery. Hard-pressed motorists have been consistently let down by this Government."

While welcoming the road plans, the RAC Foundation said the number of road users will leap from 36 million to 43 million if current trends persist.

The foundation's director Professor Stephen Glaister said the country faced "massive challenges in unclogging our urban areas".

The roads package also includes more details of the already-announced plan to turn the Highways Agency into a government-owned company. The Government says this will mean funding can be allocated on a longer-term basis, saving the taxpayer at least £2.6 billion over the next 10 years.

There will also be £100 million to improve cycling provision at 200 key locations across the network, as well as a commitment to cycle-proof any new schemes being developed.

Also, there will be a £300 million environmental fund to mitigate carbon emissions and reduce the number of people affected by serious noise by 250,000.

This fund will create new charge points for low-emission vehicles every 20 miles across the road network, as well as enhance the landscape, protect sites of cultural or historic heritage, and reduce the impact of improving the roads on wildlife, countryside and habitats, In addition there will be £100 million to unlock future growth and housing developments.

Spending during the next parliament on England's roads network will be boosted further by maintenance funding worth more than £10 billion across the local and national road network.

Chancellor George Osborne said the package would "transform some of the country's most important strategic routes", while Chief Secretary to the Treasury and chairman of the Cabinet Infrastructure Committee Danny Alexander said it would "help unleash the economic potential of both the regions they serve and of the overall economy".

Mr Clegg said: "You don't make decisions like this based on a political map, you make these decisions based on the economic map and the geographic layout of our county to make sure that all parts of our country are properly linked."

The AA welcomed the plans, saying it hoped this would mark an end to "the stop-start mess experienced over the last few decades".

The CBI said the roads strategy marked "a significant milestone in our journey towards the delivery of much-needed upgrades to our existing road network, the arteries of our economy".

But the Campaign for Better Transport said: "The plan will prove a counter-productive waste of money. There is no evidence that building new roads creates jobs or benefits the economy and plenty of evidence that it creates new traffic that just fills up the roads again."