Mediation efforts will start on Monday to try and prevent a national strike that could see petrol stations run dry.

The Commission for Conciliation, Mediation and Arbitration (CCMA) will meet with the SA Transport and Allied Workers' Union (Satawu) and the Road Freight Association over a wage dispute.

Satawu has threatened to embark on a national strike on Tuesday if no agreement was reached.

The Fuel Retailers' Association warned last week a strike by truck drivers transporting fuel could create problems.

"The infrastructure is under pressure in any event -- so a strike will cause chaos," said the association's CEO Peter Morgan.

Most petrol stations had a two-day lead time, said Morgan.

According to Satawu the strike would involve at least 30 000 workers.

Satawu was demanding a salary of R6000 per month for long distance drivers currently earning R4317 per month.

Employers were offering an overall 11 percent increase, while the union was demanding 13 percent, four months' paid maternity leave and a job guarantee on return to work.

The Road Freight Association's labour relations manager Magretia Brown said the association met with the union last Monday and Tuesday.

"But we've had no joy... however, there is a meeting set up with the CCMA on April 6," she said.

"The problem is that Satawu is asking for a wage hike of 37 percent when it comes to the long distance drivers ? and we can't afford it."