A Conservative MP was thrown out of the party in the Commons yesterday after a long-running controversy involving threats, parliamentary expenses and feuds with his local association

Bob Spink, MP for Castle Point in Essex, took the unusual step of interrupting Commons exchanges on the Budget to tell MPs that he had resigned the party whip.

But party officials swiftly disclosed that less than an hour earlier a furious Patrick McLoughlin, the Conservative’s Chief Whip, had withdrawn the whip from Dr Spink, after accusing him of issuing threats against the party.

It later emerged that Dr Spink had e-mailed the Chief Whip on Tuesday night threatening to resign unless David Cameron or other senior figures intervened to save him from a third attempt among his local members to deselect him.

He becomes the third Tory MP to lose or resign the whip in a trend that threatens to embarrass Mr Cameron and damage the party’s image. The timing is particularly unfortunate as it comes days before Mr Cameron prepares to address his spring conference in Newcastle this weekend.

Derek Conway, MP for Old Bexley & Sidcup, had the whip removed in January after he was suspended from the Commons for paying his “all but invisible” son for research while he was a full-time student.

Andrew Pelling, MP for Croydon, had the whip withdrawn last September after he was arrested on suspicion of assaulting his wife. He was never charged.

Castle Point, which covers Canvey Island, was one of only a handful of seats gained by the Conservatives in their disastrous 2001 election campaign. Dr Spink, who became the constituency’s MP in 1992, lost the seat in Labour’s landslide victory five years later but won it back after Labour’s first term with a majority of 985. He increased this to 8,201 in 2005.

Dr Spink is a “hang-em-and-flog-em” rightwinger, favouring Britain’s withdrawal from the EU and courting controversy with outspoken attacks on asylum-seekers and homosexuals and vocal criticism of abortion laws.

The Conservative Party board conducted a lengthy inquiry last year into allegations made by Dr Spink against members of his local association, but the investigation — by the former Chief Whip David Maclean and two officers from the voluntary party — found insufficient grounds for action.

The Castle Point constituency executive council had been due to vote next week on the third attempt to deselect Dr Spink. As he no longer holds the Tory whip, that meeting becomes irrelevant: a sitting MP not in receipt of the whip could not be selected as a candidate for the next election.

Dr Spink told The Times that he remained a Conservative and was planning to defend his seat as an independent at the general election. He also insisted that he resigned the party whip at his own initiative and that it was not withdrawn from him.

He said: “The Chief Whip said my resignation would disrupt the party spring conference and asked me to reconsider, or at least to delay announcement. I refused. He also asked me to meet with him, the party chairman, chairman of the [19]22 [backbench] Committee, and Dominic Grieve MP, a Tory solicitor. I did so this morning when they sought to get me to change my mind.”

Mr McLoughlin said: “I cannot have MPs making threats to resign the whip at a time of their own choosing if their demands are not met.”

Clarification

- This report may have been understood as suggesting some impropriety in Dr Spink’s private life. No such suggestion was intended. We are happy to clarify this matter and apologise to him.

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