Johannesburg - Wage talks between transport unions and the Passenger Rail Agency of SA (Prasa) continued late into Tuesday night with no sight to a "satisfactory" agreement, Utatu said.
Prasa had already upped its offer from eight to 10 percent, but negotiations were stalled by a clause in the conditions of employment, United Transport and Allied Trade Union (Utatu) general secretary Chris de Vos said at 21:00.
"It's not good to accept 10 percent now when two months from now the workers will be worse off.
"There's a specific clause in the draft agreement that will change worker conditions of employment. Once they [Prasa] remove the clause to agree with us that within two months we will change the conditions of service of some of the employees, then some movement will be made," de Vos said.
The conditions related to overtime and night shift allowances de Vos claimed Prasa wanted to do away with.
"Twelve thousand workers will be worse off... they are entitled to that."
It was not known when the parties, who had been locked in a meeting with the Commission for Conciliation, Mediation and Arbitration since Tuesday morning, would adjourn for the night.
The unions downed tools on Monday, wanting a 16 percent increase.
Utatu had threatened to take the matter to the Labour Court.
Meanwhile, about two million commuters remained stranded on Tuesday since Prasa shut down its Metrorail, Shosholoza Meyl and Autopax bus services.
- Sapa