Fair Work Australia (FWA) started on Monday court proceedings against embattled MP Craig Thomson, who is accused of using Health Services Union (HSU) credit card to pay for the services of prostitutes.

The agency filed its claims against Mr Thomson in the Federal Court. Besides allegedly paying union money for the service of sex trade workers, FWA charged the now independent MP with misusing HSU funds. FWA General Manager Bernadette O'Neill disclosed that 37 breaches of general duties on officers of registered organisations and 25 breaches of HSU rules were filed against Mr Thomson while he serve as HSU national secretary from 2002 to 2007.

The FWA charges were based on the findings of a three-year investigation that was concluded in the early part of 2012. FWA listed Young Blondes, Boardroom Escort Agency and a brothel named Tiffany's as the sex trade agencies allegedly used by Mr Thomson.

The MP has consistently denied the charges and his denial was somewhat supported by the retraction of a prostitute of her earlier statement that Mr Thomson was her former client. However, the sex trade worker said a check with her travel documents showed she was out of Australia when the alleged liaison with the MP took place.

Asked for a comment on the FWA charges against the MP, Prime Minister Julia Gillard declined to comment because the matter is already with the courts.