The Finnish Construction Trade Union on Monday postponed the start of a strike affecting Teollisuuden Voima's Olkiluoto nuclear power station site by a week to 17 September.
The union added that Rimec, a Cyprus-registered subcontractor at the site, had until 16 September to come up with an explanation of suspected wage and occupational healthcare irregularities.
According to the union, Rimec has been withholding a third of the pay of about 300 Polish workers and, despite repeated requests, failed to come up with evidence of where the money had gone.
Although the union has stressed that France's Bouygues, the main contractor at the Olkiluoto site, and its other subcontractors are beyond reproach, the strike would nevertheless affect the entire site.