Campaigners battling to halt the controversial plan to build an incinerator on the outskirts of King's Lynn have started legal proceedings, it emerged last night.

Solicitors working on behalf of opponents to the Saddlebow development have served notice on Norfolk County Council signalling an intention to challenge the decision to award a contract for the project.

The action is being taken because campaigners claim the county council had not followed the appropriate steps in awarding the contract to Anglo-US consortium Cory Wheelabrator.

But a statement from County Hall yesterday said the council had 'complete confidence' in the process it followed.

The legal challenge has been submitted by anti-incinerator campaigner Michael de Whalley and is being put together by Cambridge-based legal firm Richard Buxton Environmental and Public Law.

The firm is the same company behind a separate challenge to growth plans for thousands of new homes in the greater Norwich area, on behalf of members of Stop Norwich Urbanisation (Snub).

The move comes after environment secretary Caroline Spelman wrote to Norfolk County Council last month offering politicians more time to show public support for the proposal, which would be built under a �169m PFI (Private Finance Initiative) deal.

Government guidelines say there should be 'broad public consensus' for any PFI deal. But more than 65,000 people voted against the proposal in a referendum organised by West Norfolk Council, in February.

However, the county council agreed to press ahead and award the contract to build and run the plant to Cory Wheelabrator, on the basis that they could be exposed to a legal challenge if they changed tack on the basis of the referendum result.

However, the latest move could see the process head to the courts in any case.

County Hall, which was notified of the legal move in a letter on Monday, is likely to use its in-house law firm NPLaw in the initial stage, but will likely have to bring in outside lawyers should the High Court accept the case for a judicial review.

Mr de Whalley said: 'This is all very much a case that we feel Norfolk County Council has not listened to the community and that they have not followed the appropriate steps in awarding this contract.

'The start of these legal proceedings has sent a another clear message to the county council that we don't want this incinerator.

'It comes after the letter from Caroline Spelman, which I am sure gave the county council a great deal to think about, and their stance on the local poll, which was quite frankly unbelievable.'

Mr de Whalley also told the EDP he would be pursuing a protective costs order to limit his exposure to Norfolk County Council's costs, should he lose the judicial review.

Fellow anti-incinerator campaigner Mike Knights has welcomed this latest twist in the on-going saga.

He said: 'We believe the county council has done things it shouldn't have and that the decision to award the contract for the incinerator to Cory Wheelabrator is wide open to a legal challenge.

'I am happy that this step is being taken and I am glad a legal challenge is being made at this stage.

'If it had got to the planning stage before this step was taken, a good opportunity to stop this would have been missed.

'It would also be further down the line and there would be a lot of muscle that would be up against us.'

However, he added: 'I would rather the county council just went back to the drawing board and had another look at the other alternatives.'

Mr Knights said he believed the council was currently on 'shaky ground', but added the campaigners only wanted to see the best solution for the county's waste put forward.

He continued: 'If the county council chooses to ignore this legal challenge and press on, then I don't think it will impress the judge.

'However, I believe there is no reason to believe they won't just stick to form and continue pressing for this incinerator.'

He added: 'It is about time the county council woke up and realised what they are doing is wrong.'

Adrienne Copithorne, from Richard Buxton Environmental and Public Law, said: 'I can confirm we have issued a claim to the High Court.

'We have asked the High Court to review the legality of the decision of the local authority to award the PFI contract to Cory [Wheelabrator].'

Asked when the review could be complete, she replied: 'It depends on the work load the High Court has but it usually takes between six months and two years.

'There is, however, the possibility the council could agree the decision was unlawful and that would bring an end to the review. They can do this at anytime.'

A council spokesman said: 'Norfolk County Council can confirm that the council has received notification of action being taken to seek judicial review of the decision taken by cabinet on March 7, 2011 to award the waste PFI contract.

'The county council has complete confidence in the process it followed in deciding to award this contract.'