An impasse has meant an independent review into Norfolk County Council's contract for an incinerator at King's Lynn has yet to be commissioned – two months after councillors agreed it should happen.

But campaigners and council leaders have said a disagreement over the selection process for the QC who will conduct the review has been resolved and the report will soon be commissioned.

The council's controlling cabinet agreed in June that there should be an independent review into the contract, after the authority's own officers warned pulling the plug on the scheme could cost as much as £90m.

The cabinet invited campaigners against the Saddlebow plant to play a role in picking the QC and financial advisers who will conduct the investigation into the contract.

West Norfolk Council's leader Nick Daubney, representatives from campaign group King's Lynn Without Incineration (KLWIN) and Alexandra Kemp, county councillor for Clenchwarton and Lynn South, were invited to help pick the experts.

However, there have been disagreements over who should be on the shortlist of QCs to pick from and there have been what campaigners described as 'protracted' negotiations.

But, after the council agreed to extend the shortlist of QCs, campaigners said the QC report was 'back on track', although they said they did still have other concerns which had yet to be addressed.

Dr Martin Little, KLWIN chairman, said: 'KLWIN is working towards a report that is acceptable to either side, whatever the result.'

George Nobbs, leader of Norfolk County Council, said: 'Things had reached a bit of an impasse.

'I have gone an extra, extra mile and I'm prepared to do so if that's what it takes to heal the breach between West Norfolk and the rest of the county.'

The county council will cover the costs of the review – estimated to be between £40,000 and £120,000.

The former Conservative administration had signed a contract with Cory Wheelabrator to run the plant at Saddlebow, saying it would prevent waste going to landfill and save taxpayers' money.

But critics have questioned why other technologies could not be used and have raised concerns about the health impact of such plants.