Tory MP Caroline Spelman is in charge of regulating her colleagues' expenses
Conservative Party chairman Caroline Spelman has admitted using her MP's parliamentary allowance for payments to her children's former nanny.
Ms Spelman told BBC's Newsnight that the money, paid in 1997 and 1998, was for secretarial work the nanny did.
A Labour MP, Kevan Jones, has called for the matter to be referred to the Parliamentary standards commissioner.
Shadow Chancellor George Osborne told the BBC Ms Spelman "is someone of enormous integrity and honesty".
Mr Osbourne added that the MP for Meriden, who has recently taken charge of improving the Conservatives' record on expenses, was "the last person in Parliament" who would do something wrong.
Conservative Central Office said that the nanny - Tina Haynes - was also Ms Spelman's constituency secretary for six hours a day between 1997 and 1998 and that was what she was being paid for.
A party spokesman said: "Tina was paid from her parliamentary allowance for the work she carried out providing secretarial support in the constituency.
Clearly, old habits die hard in the Tory Party despite what their leader says
Labour MP Kevan Jones
"Tina also provided childcare outside school hours and in return for this she received free board and lodging along with use of a car provided at Caroline's personal expense.
"Following a conversation with the chief whip at the time, Caroline decided that although she had not done anything wrong, it would be better to have separate arrangements for her secretarial staffing and her childcare."
When Newsnight contacted Ms Haynes she said she took the occasional phone message and posted documents when needed.
She told Newsnight's political editor Michael Crick: "Once or twice a week you'd get the odd phone call from other MPs. Mr Hague (the then Conservative leader) rang a couple of times and obviously I took messages if he rang and passed them on."
Labour MP Kevan Jones said there was "a big question mark" over Mrs Spelman's use of allowances.
He added: "Clearly, old habits die hard in the Tory Party despite what their leader says."
Mr Jones said that if Ms Spelman could not provide a satisfactory explanation, the Parliamentary Commissioner for Standards may need to investigate whether she had broken rules which prohibit MPs spending their allowances on activities not directly related to their jobs.
Newsnight interview Caroline Spelman's former nanny
The allegations have come at a sensitive time for both the Conservatives and Ms Spelman, who played a role in prompting the resignation on Thursday of Tory MEP leader in Brussels, Giles Chichester.
Mr Chichester stepped down as leader after Ms Spelman asked him to answer allegations that he had broken European Parliament rules on expenses.
The party's chief whip in Brussels, MEP Den Dover, has also been replaced after he denied breaking any rules in paying his wife and daughter a reported £750,000 for work over nine years.
The Tories say the move is unrelated to the issue of expenses and was normal after a change of leader.
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