Conor Burns has resigned as trade minister after a report found he had used his parliamentary privilege “in an attempt to intimidate a member of the public“.

The MP for Bournemouth West had been trying to resolve a financial dispute on behalf of his father. In correspondence to the complainant, he wrote on House stationary: “I am acutely aware that my role in the public eye could well attract interest especially if I were to use parliamentary privilege to raise the case”.

The Parliamentary Commissioner for Standards concluded that “the letter to the complainant was concerned solely with a personal financial situation and was not sent in support of his parliamentary activities”, and therefore in breach of the rules.

The Committee unanimously accepted the Commissioner’s report and considered mitigating factors, such as that: “Mr Burns had been under a considerable degree of personal stress, and that he had apologised for the Committee.”

But it still found that he had “persisted in making ill-disguised threats… even after the Commissioner had informed him that this was a serious breach of the rules.”

The Committee recommended that Burns should be suspended from service of the House for seven days, and that he should write an apology to the Speaker of the House and to the complainant as the injured party.

On Twitter, Burns wrote that he had made the decision to resign with “deep regret”, having been appointed to the role in July last year. No 10 said Burns would be replaced “in due course”.