More than 400 Nepalese migrant workers have reportedly been killed on Qatar's World Cup building sites as the Gulf state prepares to host the event in 2022, a report is expected to reveal this week.

The figures are due to be published by the Pravasi Nepali Co-ordination Committee, a human rights organisation and will add to calls for the Qatari authorities and football governing body Fifa, to improve safety.

Qatar, like other states in the Gulf, relies heavily on migrant workers, mainly from Nepal, India, Bangladesh, Pakistan and Sri Lanka.

Qatar's World Cup authorities recently published a Workers' Welfare Standards report, which provides a breakdown of the guidelines that 2022 organisers expect contractors and sub-contractors to observe.

Jim Murphy, Labour's shadow international development minister, has raised concerns. He wrote recently: "People don't have to die to bring us this or any other World Cup or sporting event; not a single worker died building the sites for the London 2012 Olympics."