Unveiling the plans Alistair Darling listed road schemes for 92 "pinchpoints" to be undertaken across the UK.

These are intended to improve conditions on trunk roads and motorways and will be carried out by the Highways Agency within the next five years.

(The package) will address some serious bottlenecks on the motorway and trunk road network which currently cause major delay

Alistair Darling

The work will be carried out on the most heavily used motorways and A roads around cities such as Birmingham, Nottingham, Peterborough and Manchester.

But most of the improvements will be small scale.

They will involve creating new roundabouts and changes in lane markings to keep traffic flowing.

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

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

Focus of improvements

Birmingham Nottingham Peterborough West Manchester M25 north of London Roads to south coast ports

He stressed the need to "strike the right balance between the need to use roads and the wider considerations", including the use of rail travel.

The list concentrates on the most congested sections of the major motorways and A roads - in particular around Birmingham, Nottingham and Peterborough and west of Manchester.

Several junctions on the M25 north of London will be improved, as will the approaches to some of the south coast ports.

Ministers are hoping this sort of initiative will ease the pressure of traffic while they consider a string of decisions about proposed new roads.

Repackaged

But some of the government's critics have accused it of tinkering while the country grinds to a halt.

The UK is the fourth largest economy in the world yet we compare (in transport investment terms) unfavourably with Portugal, Ireland and Spain

Richard Turner, Freight Transport Association

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

He told BBC Radio 4's Today programme: "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."

The plans have been given a cautious welcome by motoring organisation the AA.

Paul Watters, head of roads and transport policy, said parts of it were simply repackaged old schemes, and much more needed to be done.

London constraints

Speaking earlier on Wednesday, Mr Darling said Wednesday's announcements were the first of a number of measures designed to "bear down" on congestion problems.

"Problems vary, they are intense in some parts of the country less in others," he told the Today programme.

Asked his opinion on the forthcoming introduction of congestion charges in London, Mr Darling said: "Any constraint has to have popular consent.

Alistair Darling: Says measures consistent with environment improvement

"The Mayor of London has got to ask whether the scheme he is introducing has got that."

BBC transport correspondent Tom Symonds says the big decisions have not been made - in particular whether to build a string of new roads and bypasses, and whether to widen a number of A roads.

The government has also got to decide whether it wants to persuade drivers out of their cars by charging them to use busy roads.

So far apart from London, there are no plans to do so.