Ministers are preparing to commit hundreds of millions of pounds of public cash to prevent the collapse of a billion-pound plan to widen the M25.
The financial crisis has arisen after fears that ConnectPlus, the private contractor likely to undertake the works, will announce a shortfall in private funding for the project.
As a result, the Government is preparing to inject cash to underwrite the scheme. It is estimated that the taxpayer could be asked to pay up to 400 million towards the scheme.
The M25 project encompasses the maintenance and widening of around 65 miles of the M25 and is one of the largest ever road projects in the UK.