General Motors says it has had to suspend production at its main South African plant in the coastal city of Port Elizabeth as a nationwide strike over wages means it cannot get parts to build vehicles.
South Africa’s National Union of Metalworkers – with nearly a quarter on a million members – has been on strike since Tuesday.
The union rejected an increased wage offer from the Steel and Engineering Industry Federation on Thursday.
The employers offered wage increases of up to 10 percent, revised from eight percent previously. The union wants hikes of 12 to 15 percent, more than double the inflation rate
There has been violence on picket lines outside some factories.
GM is the latest victim of widespread labour unrest in South Africa, which has hit the economy hard and made investors wary.
They are increasingly frustrated by the unremitting industrial strife and perceptions that the government is unable, or unwilling, to rein in militant unions.
A five-month walkout in the platinum industry ended only last week.