Many township petrol stations across the country have run out of fuel as the road freight industry strike continues on Friday, the SA Fuel Retailers Association (FRA) said.

"The most affected areas are townships throughout the country because of safety issues. Truck drivers fear intimidation in those areas, so we are calling on companies to beef-up security," said Safrea CEO Reggie Sibiya.

On Thursday most complaints were received from Shell and Chevron. Sibiya said Shell was affected and Chevron was "catching up".

"Engen is still on top of its game so far and we've had no complaints from other members of the association like BP and Sasol," he said.

Sibiya said the most-affected depots were in Witbank, Pretoria, Johannesburg, and Durban because of backlogs.

"These depots are struggling to keep up with the backlog."

The strike in the road freight industry started on Tuesday.

The Road Freight Employers' Association (RFEA) announced on Thursday that it had reached an agreement with Satawu on wage issues.

Satawu was now demanding that the wage agreement be extended to employees not covered by the bargaining council, such as data capturers and administration staff, RFEA spokeswoman Magretia Brown said.

Satawu denied in a statement on Thursday that any agreement had been reached.

"Satawu wishes to clarify media reports suggesting that an agreement had been reached last night with the RFEA on 11 percent across the board.

"We categorically state that there was no agreement reached or signed by Satawu negotiators."

According to Satawu, the reports were intended to create confusion and mislead its members on the ground.

It added that its members in the road freight industry would continue to strike.

"Satawu calls for maximum unity and discipline from all its members in pursuit of our legitimate demands," the union said.