SYDNEY (AFP) - Former Australian prime minister Julia Gillard on Wednesday denied any wrongdoing regarding a fund used for allegedly fraudulent purposes as she was grilled at an inquiry into union corruption.

Ms Gillard, who was ousted as Labor Party leader last year, has long been dogged by her actions in helping create the fund set up by her former boyfriend, Australian Workers Union official Bruce Wilson.

At the time, in 1992, she was a lawyer with Slater and Gordon and provided free legal advice to the union, including on a fund called the Workplace Reform Association, which was supposed to raise money for union elections.

Witnesses at the Royal Commission into Trade Union Governance and Corruption have claimed that thousands of dollars were misappropriated, with money used by Mr Wilson to help buy a house. There have also been allegations that he gave then girlfriend Ms Gillard cash from the fund to pay for renovations to her home.

Ms Gillard has always strenuously denied acting improperly but admitted to the inquiry that in hindsight she would do things differently.

"None of us get to go in a time machine and go backwards," she said. "Obviously, if one got to do the whole thing again, you would do things differently, given what I know now that I did not know at the time."

She has previously blamed "a smear campaign" for rumours that money from the fund was used to help her and on Tuesday said she had no recollection of ever receiving cash in her account from Mr Wilson.

"All payments made for renovations on my property were from my own money," she told the inquiry.

Ms Gillard forged a career in industrial relations law before moving into politics. She entered the House of Representatives in 1998 and became the country's first female prime minister in June 2010.

The royal commission, established by the current conservative government in March to examine alleged financial irregularities associated with trade unions, is due to report its findings in December.