A British man has died working on World Cup stadium building site in Qatar, where construction conditions have come under sharp scrutiny since the country was awarded the 2022 football tournament.

World Cup organisers did not name the 40-year-old man or provide any details of the incident, saying only that he "lost his life working" on Thursday at the Khalifa International Stadium, which will also host the world track championships in 2019.

The project to renovate the stadium, which is described by organisers as "Qatar's most historic stadium," is being supervised by Belgium company Besix in partnership with local company Midmac Contracting. There was no immediate comment from Besix.

"The relevant authorities have been notified and the next of kin has been informed," Qatari World Cup organisers said in a statement. "An immediate investigation into the cause of this fatality is underway and further details will be released in due course. The Supreme Committee for Delivery and Legacy shares our deepest condolences with the family for their loss."

Qatar has previously announced the death of four stadium workers, with one fatality the result of a work-related accident.

The focus of the scrutiny has been on Qatar's use of a low-paid, migrant workforce to build the sites for the first World Cup in the Middle East, but the organisers are also relying on expertise from Europeans to oversee projects.