Caroline Spelman, the Tory chairman, was under renewed pressure last night after it was alleged that her own secretary first raised concerns that she was using her parliamentary expenses to pay her nanny.

Newsnight, on BBC Two, said that Sally Hammond — who became a part-time secretary to Mrs Spelman in 1999 — was “shocked” to discover how much she was paying Tina Haynes. According to the programme, she is prepared to give evidence to the inquiry by the Parliamentary Standards Commissioner into the affair, which would appear to contradict Mrs Spelman’s account.

Ms Haynes was employed by Mrs Spelman when she became an MP in 1997 to look after her children and do secretarial work. According to Newsnight Mrs Hammond found that Ms Haynes did little or no secretarial work to justify the payments.

The episode has added to David Cameron’s embarrassment because Mrs Hammond is the wife of Stephen Hammond, the Tory frontbencher. She was said to have become aware of the situation because she could not understand why Mrs Spelman had so little money available for office expenditure. A party spokesman would say only that Mrs Spelman was co-operating fully with the inquiry.

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