Australia's five-time Olympic gold medallist Ian Thorpe will sue the French newspaper L'Equipe and one of its journalists for defamation over a drugs controversy, his spokesman said Monday.

The French sports newspaper in March last year published details of a urine sample Thorpe returned in May 2006 that showed abnormal levels of testosterone and leutenising hormone.

The Australian Sports Anti-Doping Authority subsequently found Thorpe had no case to answer and international swimming body FINA said there was insufficient evidence he took performance-enhancing drugs.

But despite being cleared, Australia's most successful Olympian said his reputation had been irreparably tarnished by the allegation, which came just months after he retired from a sport he had dominated for most of a decade.

"Ian Thorpe intends to pursue the legal proceedings for defamation that he has commenced in the court against French newspaper L’Equipe and a journalist from that newspaper, Damien Ressiot," spokesman Jason Allen said in a statement.

Thorpe’s lawyer Tony O’Reilly had informed the New South Wales Supreme Court of this on Monday and said that the proceedings would include a claim for infringement of privacy, the statement said.

The court proceedings were adjourned until September 22, when it was expected that preparations would be made for a hearing some time next year, the statement said, adding that no further comment would be made.

Shortly after being cleared last year, Thorpe told reporters: "My name is forever tarnished, more so overseas than what it is here, and that's something that I continue to have to deal with."