Some 70 000 workers on Monday won the right to strike at construction sites of World Cup stadiums, the National Union of Mineworkers (NUM) said.

"The Labour Court has this morning [Monday] ruled in favour of the NUM and dismissed the case with costs. Over 70 000 construction workers will on Wednesday down tools," said NUM spokesperson Lesiba Seshoka in a statement.

The SA Federation of Civil Engineering Contractors applied last week for an interdict to halt the mass action.

The decision to strike followed a deadlock in wage negotiations mediated by the Commission for Conciliation, Mediation and Arbitration.

Construction projects likely to be affected by the industrial action included the Moses Mabhida, Nelson Mandela, Soccer City and Mthatha stadiums.