The full bitter extent of the division in Norfolk's Conservative leadership caused by the proposed incinerator at King's Lynn has been laid bare.

All seven Tory MPs for the county have signed a formal letter of complaint to the Conservative leader of the county council, Derrick Murphy, after taking strong exception to a warning that MPs objecting to the planned incinerator at Saddlebow could see the loss of council-funded spending projects in their constituencies.

Having received that message, Henry Bellingham and Elizabeth Truss, the MPs for North West and South West Norfolk, referred it to the authorities of the House of Commons on the grounds that there was an 'implied threat' to them in their work and that it possibly constituted a breach of parliamentary privilege.

A contempt of parliament can be caused by 'threatening to end investment by a public corporation in a member's constituency if the Member persisted in making speeches along the lines of those in a preceding debate'.

The Office of the Clerk of the House told the EDP that its advice to MPs is confidential. But it is understood that its conclusion was that the letter to Mr Bellingham and Mr Truss only narrowly failed to offend against the rules.

Sent by the council's deputy leader Ian Mackie on November 22, it said that the decision by environment secretary Caroline Spelman not to provide PFI credits from the controversial incinerator would 'remove a �200m saving for all Norfolk taxpayers'.

It also stated that 'any influence you (Mr Bellingham and Ms Truss) may have in persuading the secretary of state to withhold the PFI credits, which had previously been allocated, will have significant financial consequences for Norfolk as a whole'.

It added that the council had to make contingency plans 'during this period of financial uncertainty'. And in a section that particularly troubled not only Ms Truss and Mr Bellingham but all the Norfolk Conservative MPs, Mr Mackie stated: 'Whilst the county council is committed to its �1.5m grant to the College of West Anglia, we have to pause our financial support for the NORA (Nar Ouse Regeneration Area) housing development project and the Thetford Riverside Regeneration Project, some �1m investment. Until we gain certainty of our PFI credits we will not be able to release that funding.'

The NORA scheme is for the building of over 150 houses in Lynn in Mr Bellingham's seat, and the Thetford proposal is in Ms Truss's.

In their letter to Mr Murphy - which read like a declaration of civil war between Norfolk's Tory representation at Westminster and the party's leadership at County Hall - the MPs said 'we do not view it as acceptable under any circumstances that there should be a targeted removal of funding when a local MP disagrees with the views of the county council'. And it continued: 'We are sure that our constituents would be shocked at the implications behind that threat.'

Mr Mackie's letter was sent about two weeks after Ms Spelman had caused shock and horror at County Hall by her decision on the incinerator PFI credits. An already angry schism over the issue in Tory circles in Norfolk was taken to greater levels of toxicity.

None of the MPs would comment publicly last night on the 'private' but leaked letters.

Mr Murphy told the EDP: 'I have yet to receive any such letter so it is difficult for me to comment in detail on something I haven't seen.

'It is a matter of public record we have put the funding for some projects on hold until we know whether or not we are to receive a government grant worth �169million. We will have to re-prioritise some of the projects we support if we don't receive it - especially in the current economic climate.

'I know the deputy leader's letter explaining the financial facts was never intended to be threatening in any way. We greatly value our strong relationship with Norfolk's MPs and I am very sorry if it gave that impression because we have been working so well with them on a wide range of issues crucial to Norfolk's future.

'Clearly when I actually receive the letter, I will respond directly to further reassure them on this point.'