An Australian Treasury Department official of Maltese descent has admitted before a parliamentary committee that he was behind an email which has caused a political furore in Australia.

In the e-mail, the Australian Prime Minister's economic adviser, Andrew Charlton, purportedly sought Mr Grech's help in seeking special treatment for car dealer John Grant, who was a donor of the ruling Australian Labor Party.

Godwin Grech told The Australian newspaper that he created the fake email and passed the contents to Opposition leader Malcolm Turnbull.

He insisted, however, that the contents of the e-mail were his recollection of an original email from the office of Prime Minister Kevin Rudd urging government help for Mr Grant.

The original email could not be traced.

Mr Grech is also alleged to have written questions for the Opposition Leader to ask in Parliament about Mr Rudd's denials that he had not sought special favours for Mr Grant.

The Australian governemnt is calling for the Opposition leader to resign if his allegations are not substantiated.