"The Utatu and SA Railways and Harbour Workers' Union alliance, representing 54 percent of members in Transnet, signed the wage agreement which will be implemented immediately and backdated to April 1," Utatu said in a statement.
According to the agreement, the basic pensionable salary for Transnet employees falling within the bargaining unit would increase 11 percent across the board.
Utatu called on all its members to report for duty from midnight.
The SA Transport and Allied Workers' Union, representing 39 percent of workers at the parastatal, rejected Transnet's 11 percent offer.
It would mobilise other sectors for a solidarity strike, union president Ezrom Mabyana said on Friday afternoon.
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