Call the cops over budget leak: Robb

The Coalition has called on the federal police to investigate the leaking of a Treasury document that suggested an $800 million black hole in its campaign costings.

The Coalition has called on the federal police to investigate the leaking of a Treasury document this week which suggested the opposition had an $800 million black hole in its campaign costings.

"I have approached the Australian Federal Police commissioner today to request an investigation into the source of a leak of confidential Treasury analysis to The Sydney Morning Herald," coalition campaign spokesman Andrew Robb said in a statement.

"As a result of (Treasurer) Wayne Swan's refusal to address this most serious issue, the coalition has been left with no alternative other than to directly approach the AFP regarding our concerns."

Mr Robb said Labor had not hesitated to call in the federal police in the past to investigate suspected leaks from the Treasury.

Last year the AFP discovered that ex-Treasury official Godwin Grech had forged an email which he then leaked to then Opposition Leader Malcolm Turnbull.

Mr Grech had previously leaked real departmental documents to the coalition over a number of years.