Campaigners from the UK's leading environmental groups are joining forces to fight plans for a multi-million-pound road linking two towns.

They claim the proposed 5.6km road between Hastings and Bexhill would damage one of Britain's most important wildlife sites.

Supporters claim a link road would bring housing, investment, jobs and sorely-needed economic activity to an area ranked the 28th poorest in Britain.

However, the proposed £47 million road from the A259 in Bexhill to Queensway in St Leonards passes near Combe Haven, a site of special scientific interest (SSSI).

Six possible routes were looked at, with construction costs ranging from £50 million to £145 million, and 65,000 people were asked for their views.

Tory-run East Sussex County Council chose the so-called blue route and has submitted a bid for funding to the Government which will make its decision in December.

Fierce opposition has come from the Hastings Alliance, an umbrella group of national and local organisations, which claims their research shows the road would undermine efforts to regenerate the area because businesses might move from the town centre.

And they fear that although the proposed route does not pass directly through ancient woodland there would still be secondary impacts on wildlife.

Friends of the Earth executive director Tony Juniper said: "This is one of the most damaging and unnecessary road proposals in the entire country.

"The council should abandon this crazy scheme and investigate alternative ways of dealing with the area's transport problems."

Sean Spiers, chief executive of the Campaign to Protect Rural England, said: "This road may just avoid designated sites but it will still have a devastating impact on the character of the whole area."

Plans for a link road were put forward after the Government rejected a controversial bypass scheme in Hastings and Bexhill three years ago.

The green lobby claims the fresh proposal is a bypass under a different guise and Friends of the Earth has urged councils to reconsider the "costly and damaging" scheme.

Chris Corrigan, South-East regional director of the RSPB, said: "There are already serious questions as to whether the road can deliver the benefits it promises.

"To sacrifice parts of our precious countryside on the off-chance of economic success cannot be sustainable."

County council leader Peter Jones said 86 per cent of the public had voted in favour of a link road. It was vital to relieve congestion along the A259 Bexhill Road, St Leonards, where carbon monoxide emissions are high, posing a threat to people living there.

The road would open up strategically-important land for housing and business development.

Coun Jones said the link road was important for the new university in Hastings which is to run computer degree courses, giving blue-chip companies an incentive to move to the area.