Construction firms working on the A4 motorway between Delft and Schiedam have ended their contract with subcontractor Rugovac with immediate effect because of the way the German firm is exploiting its workers.

The consortium, made up of Dutch construction firms Heijmans, Boskalis and VolkerWessels, brought in an independent accountancy and administration group to investigate following union complaints.

That research shows that Rugovac has not acted properly, its paperwork is not up to scratch and workers are not being paid official pay rates, news agency ANP says.

Workers will continue to work on the project but for a different subcontractor.

Another road project, a tunnel on the A2 motorway near Maastricht, has also been hit by a dispute over the payment of workers brought in by a subcontractor.