The NAO, and its chief Sir John Bourn, are to be probed by the Public Accounts Commission in relation to spending concerns.

The commission's inquiry will look at 'the extent to which the NAO's corporate governance arrangements are consistent with best practice elsewhere'.

The comprehensive investigation will also propose any necessary improvements, taking account of the need to safeguard Sir John's 'statutory discretion in carrying out his duties'.

Also on the agenda will be whether the NAO should be overseen by a separate advisory board staffed with new non-executives.

PAC member Richard Bacon said: 'MPs on the commission are concerned about the level of scrutiny of the National Audit Office itself.'

Further reading:

NAO audit committee chair to vet Sir John Bourn's expenses