The French footballer who said he was left stranded for 17 months in Qatar because of a financial dispute with his club has filed a lawsuit against the side, his lawyer said on Friday.

The complaint on behalf of Zahir Belounis, of which Reuters obtained a copy, alleges "fraud, inhuman working conditions, forgery and aggravated extortion of money" against Al-Jaish.

Belounis, 33, who joined the Qatari club in 2007 and signed a new five-year deal in 2010, alleged he had been denied an exit visa after bringing a court case against Al-Jaish over two-and-a-half years of alleged unpaid wages.

The player said he was being prevented from leaving Qatar because his employer would not grant an exit visa - which is required in Qatar - unless he dropped the case.

He eventually left the country last month after agreeing to sign a backdated resignation letter stipulating that he will not be paid for the two remaining years of his contract, estimated to be around 120,000 Euros ($164,800).

The Belounis case was taken up by the international players union FIFPro who said it hoped publicity would help to change the sponsorship system that linked a working permit to a single employer, a system criticised by human rights groups and the United Nations.

His plight is another controversy dogging 2022 World Cup hosts Qatar following an outcry over the treatment of migrant workers in the Gulf state's construction industry.

The club could not be reached for comment.