Dutch firms have earned millions of euros on building projects linked to the forthcoming football World Cup in Qatar, according to research published on Tuesday in Trouw.

Some firms have earned tens of millions of euros from their work, the paper said. Construction giant BAM, steel company Frijns Staal, Royal HaskoningDHV, dredging firm Boskalis civil engineers Arcadis are among the firms the paper said had been working in the Gulf state.

The companies have been involved in building a metro station for football fans, have worked on the airport and on the construction of a new city, complete with football stadium, the paper said.

The Qatar World Cup has become an extremely controversial project, given that some two million labourers have been brought in to carry out the work, often in extremely poor conditions. Several thousand of them have died.

Trouw said it did not know if anyone involved in the Dutch projects had died.

Not all the Dutch firms which were involved in Qatar carried out any research into working conditions before making the move, the paper said.

A number of sponsors of the Dutch national football squad have said they will not be attending the event, including ING, Albert Heijn, KPN, and lottery company Nederlandse Loterij.