A complaint has been made to Communities Secretary Eric Pickles over a telephone poll purporting to show support for the building an incinerator.

Ray Harding, chief executive of West Norfolk council, has written to Mr Pickles, asking him to give 'due consideration' to concerns over the results, when he makes the final decision on whether the incinerator should go ahead.

Burner firm Cory Wheelabrator commissioned the survey, carried out polling firm ComRes, in February 2011. Results, which were used to support a planning application, appeared to show that people were given six alternatives, including whether they would prefer more waste to be recycled.

Campaigners from the King's Lynn Without Incineration group claim people contacted by ComRes were only given four options, which did not include recycling - landfill, generating energy from waste, other and don't know.

In a statement, ConRes has confirmed that only four questions were asked. It adds 'commonly recurring' responses to the option 'other' were included in the poll results. It said it would not have made sense to include recycling, as the survey asked people what should happen to waste which could not be recycled.

A final decision over the incinerator is expected in the New Year. Norfolk County Council gave the plant planning permission, in 2012.

But the decision was called in Communities Secretary Eric Pickles, who is awaiting the recommendation from the inspector who chaired a public inquiry earlier this year before making his financial decision.

The future of the plant was thrown into doubt in October, when the government announced it was withdrawing £169m in PFI credits because it was no longer needed to meet its targets for diverting waste from landfill.

But Norfolk County Council has since voted to press ahead, saying it could not afford penalties of more than £20m it would have to pay Cory if it cancelled the contract.