Johannesburg - Petrol stations may run dry as fuel workers embark on a countrywide strike on Monday, the Fuel Retailers' Association (FRA) said.
"In terms of determining when it will run dry depends on how organised the strike is," chief executive Reggie Sibiya said.
"But we are not going to see it today as most stations have stock."
Sibiya urged motorists not to panic but be prepared for fuel shortages.
"Hopefully, unions and employers reach a speedy resolution."
About 70 000 fuel workers from the Chemical, Energy, Paper, Printing, Wood, and Allied Workers Union (Ceppwawu) and the General Industries Workers Union of SA (Giwusa) were demanding a minimum salary of R6 000 per month and a 40-hour work week.
Giwusa president Charles Phahla on Sunday told reporters that workers would march to the Chamber of Mines in Johannesburg, on Tuesday.
He believed fuel and medicines would be in short supply.
Last week, about 170 000 engineering and steel workers from the National Union of Metalworkers of SA (Numsa), the Metal and Electrical Workers Union (Mewusa), the United Association of SA (Uasa), Solidarity, and the SA Equity Workers Association (Saewa) began striking.
They were demanding wage increases ranging from ten to 13%, and a ban on labour brokers.
Violence had erupted with one death and six injuries reported.