Johannesburg - Wage talks between four transport unions and the Road Freight Employers' Association (RFEA) deadlocked on Friday.
RFEA spokesperson Catherine Larkin said the parties could not reach an agreement after two days of negotiations.
"The parties are deadlocked with the unions at 9% and the association at 7%," she said.
Larkin said the unions had rejected several offers the RFEA had proposed.
Its latest offer was to increase existing allowances by 6.5% with additional remuneration for drivers who transported hazardous substances.
"We believe that this offer is reasonable based on current economic indicators and are disappointed that the unions remain at their current position," Larkin said.
The SA Transport and Allied Workers' Union, the Motor Transport Workers' Union, the Professional Transport Workers' Union (PTAWU) and the Transport and Allied Workers' Union rejected the offer.
PTAWU general secretary Reckson Baloyi said the unions would embark on a protected strike in September, once they had been issued with a certificate by the Commission for Conciliation, Mediation and Arbitration.
He warned that ATMs could run dry because cash-in-transit companies would be affected and that petrol stations could be left empty.
"Our economy desperately needs road freight to assists with supply of goods, passenger transported and money distribution to and from the clients such as retailers." said Baloyi.
The association said that although no further meetings were scheduled, it remained committed to resolving the dispute.
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