Johannesburg - A "secondary strike" by port workers represented by the SA Transport and Allied Workers' Union (Satawu) will take place over three days next week, Transnet said on Tuesday.
Transnet had been previously given notice that Satawu planned a one-day strike for both rail and port workers, the company said in a statement.
However, the company said it had now been told by Satawu that the labour action for port workers would be three-days, while the rail worker strike would remain a one-day strike.
"Transnet is considering the validity of the notice, including whether it meets all the requirements of a strike of this nature, and it will activate contingency measures to ensure minimal disruptions should the action materialise," it said in the statement.
Satawu said the downing of tools by port and rail workers was in support of an ongoing, two-week strike by truck drivers.
Negotiations between unions representing the truckers and employers broke down on Tuesday afternoon.
The strike began on 24 September and has left several trucks destroyed, people injured and - as of Tuesday morning, - at least one person dead.
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