Mr Tripodi was accused of the breach after letters to political donors were leaked to the Opposition by Labor sources showing that Mr Tripodi used his letterhead as Fairfield MP to thank at least three donors for their payments in March 2004.

Other documents also showed he held campaign committee meetings in his electorate office on several dates in 1999 and 2004. At least one of these meetings involved Chris Bowen, who is now the federal Assistant Treasurer.

The Opposition referred the documents to the Speaker, Richard Torbay, who asked the clerk of the Legislative Assembly, Russell Grove, to investigate the matter. Late yesterday, Mr Torbay released a statement that said despite Mr Tripodi breaching the parliamentary guidelines for MPs' use of resources, there was no need for any further investigation.

"The use of a member's parliamentary letterhead and envelopes in relation to a local government election campaign are in contravention of the Parliamentary Remuneration Tribunal rules," the statement said.

"As electorate offices are public-funded resources, they are also not permitted to be used for campaigning or electioneering."

But the statement said that while Mr Tripodi had committed a clear breach, "on the information received, Mr Tripodi's activities in 2003-04 would not appear to be a substantial, fraudulent or systematic breach of the guidelines, to the extent that external investigation would appear warranted at this time."

The statement said that a formal response had been sought from Mr Tripodi, who has offered to repay any expenses.

"While the value of the resources utilised for campaigning was minimal, the issue at the basis of these rules is a prohibition on use of public funds available to incumbents," the statement said.

Mr Tripodi, who is in Tokyo on government business, released a statement saying he accepted the findings of the investigation.

"The Speaker has noted that there was no substantial, fraudulent or systematic breach of the parliamentary guidelines," Mr Tripodi said.

"I once again apologise for this oversight and I will pay back whatever is required."

The Opposition Leader, Barry O'Farrell, said the rules were clear and taxpayer-provided resources and facilities should not be used to help run Labor's local council campaigns.

"I am concerned this is just the tip of the iceberg," Mr O'Farrell said.

"After 14 years in office, Labor MPs like Joe Tripodi are incapable of separating their public duties from ALP activities."