Ambitious plans have been unveiled to reduce traffic congestion at four key road junctions in Sussex.

Transport secretary Alistair Darling said the work, which will take place over the next five years, would cut journey times and reduce pollution.

The emphasis will be on making better use of existing roads, rather than building new ones.

Projects unveiled by Mr Darling include new roundabouts on the A21 at John's Cross, near Battle, and the A21 at Moat Lane, Hastings.

Road improvements will be carried out at the Gatwick junction of the M23 and traffic signals will be fitted on the A27 in Worthing.

The improvements are among 92 projects announced by the Government to improve key roads across Britain.

Mr Darling said: "The Government is committed to tackling congestion and reducing the number of accidents on our roads.

"The package will address some serious bottlenecks on the motorway and trunk road network, which currently cause major delays.

"Improving these junctions will cut queues and improve traffic flow, leading to more reliable journey times and less pollution."

Some of the Government's critics have accused it of tinkering while the country ground to a halt.

Richard Turner, chief executive of the Freight Transport Association, said the Government was still not spending enough on transport networks.

He said: "The UK is the fourth largest economy in the world, yet we compare unfavourably with Portugal, Ireland and Spain.

"We really believe the British economy deserves better than that."

Paul Watters, head of roads and transport policy for the AA, said the improvements were simply repackaged old schemes and much more needed to be done.

Shadow transport secretary Tim Collins took issue with Mr Darling's methods of tackling Britain's transport problems.

He said: "There probably are more things that need to be done to close some of the gaps in our motorway network rather than just the very welcome but small-scale announcement that Alistair Darling has made."

Mr Collins also stressed there was strong Conservative opposition to congestion charging, which has been suggested for Brighton and Hove.

A £2 charge to enter the city forms part of a £1 billion package of plans mapping out the future of transport in the South-East for the next 20 years.

Mr Collins said it was "extraordinary" that Mr Darling was pretending congestion charging had nothing to do with the Government, which had already handed Ken Livingstone, the mayor of London, the power to impose it in the capital.

He said: "Conservatives across the country, not just in London, are opposed to congestion charging.

"It is a flat-rate tax so it hits the poor as well as the rich.

"It is very inefficient at collecting revenue and is going to cost more in the first year than the revenue that is going to be raised from it.

"And it does not actually work."