South Africa’s labour court has ordered workers at ArcelorMittal South Africa’s (AMSA’s) steel plants, blast furnaces and coke batteries to be excluded from an ongoing job boycott, after the company argued these are essential services barred from striking by law, the metal-workers union said. The National Union of Metalworkers of South Africa (Numsa) began a strike at Africa’s biggest steel company on Wednesday, after wage negotiations broke down last week.