Former head of the NAO Sir John Bourn suspects a discontented colleague may have been responsible for tipping off journalists about his expenses spending.

Sir John, who left his post last week, said his resignation was not connected to the issue, and that he had made the decision to leave after 20 years due to a potential conflict of interest.

'We are all potential victims of disaffected employees or ex-employees,' he told The Daily Telegraph. 'I've not got the evidence to back this up, but I think the original raising of the issue has been by someone who used to work for this office.'

Sir John's expenses have been the subject of intense interest after it emerged that he lunched with contacts at all the best restaurants in London, and that he and his wife stayed in expensive hotels when abroad at taxpayers' expense.

Sir John insisted all his expenses had been properly incurred, and pointed out that auditors had scrutinised his accounts and concluded that there had been no impropriety in his spending.

Further Reading:

Read the Telegraph interview