An internal political war is continuing in a North Yorkshire constituency – with an open letter to members of a local Conservative association urging them not to reselect their current MP.

The letter, jointly written by local members George Winn-Darley and Victor Buchanan, demands an end to a “poisonous situation” and levels various criticisms at Thirsk and Malton MP Anne McIntosh.

It comes as ballot papers were due to be sent out to all 560 association members to decide who should defend the Tories' majority of more than 11,000 at the next general election.

Miss McIntosh, 59, said she would not comment on what was a democratic internal party process, but would be delighted to do so once the ballot results was known.

In the letter, Mr Buchanan and Mr Winn Darley say: “We believe Thirsk and Malton deserves a more effective MP. “Many constituents feel Miss McIntosh’s responses on issues raised directly with her have fallen short of what they expected and that she has displayed poor judgement on key local issues.”

They also claim promises made after a previous 2009 deselection meeting to improve communication and access to her diary were not kept.

“We believe it is untenable to have an MP who cannot work with her local party.

“Opinion may differ as to Miss McIntosh’s record as a politician, but no one can deny that these divisions have gone on far too long.

“With regret, we say that this poisonous situation cannot be allowed to continue.”

Miss McIntosh, who is chairman of the influential Environment, Food and Rural Affairs Select Committee has been involved in a year-long battle, after the executive of Thirsk and Malton Conservative Association voted last January against automatically readopting her as their candidate.

Party chiefs later said the decision was technically invalid.

This summer supporters presented a 300-signature petition to Downing Street calling for her to be automatically readopted.

Last month she was one of just two MPs in the region to pledge she would give away a proposed £7,600 pay increase to charities and good causes.

Ballot papers were due to be sent out today with the result, which will be binding, due on January 31.