JOIN USA prolonged strike could cause the partial shut down of an economy in recession and could scare foreign investors.
Several sectors in Africa's biggest economy are holding wage negotiations, some of which cover a two-year period, and unions are demanding above-inflation increases.
Employers have balked at the demands, with consumer inflation at eight percent, citing the global economic downturn.
As well as World Cup infrastructure, the construction strike could halt work on the mass transit Gautrain high-speed rail project, power stations, an airport, a refinery, a coal terminal, hospitals, highways and mining projects.
Collapsed talks
The National Union of Mineworkers said it had served the construction sector's employer body with a notice to go on strike after prolonged wage talks collapsed last Friday.
Over the past two weeks, South Africa has staged the Confederations Cup, a test event for the World Cup, which whetted the appetite for the main event, but a lot of work was still pending, including completing building works on stadiums.
FIFA president Sepp Blatter gave organisers of the Confederations Cup a mark of 7.5 points out of 10 on Monday.
There was no immediate comment from the government on the possibility of a strike, but earlier on Tuesday it said the success of the tournament had put to rest all doubts that South Africa would deliver a successful 2010 FIFA World Cup.