Motorists should brace themselves for an increase in the price of petrol when the Department of Minerals and Energy releases fuel prices for May on Thursday.
The Central Energy Fund said on Friday the figures, which are usually released on the last Friday of the month, would now be published on Thursday.
A fund official said the release of the figures was delayed because "there were many public holidays this month".
The petrol price is expected to increase by between five and 10 cents as international oil prices gain strength, while the rand has also performed well towards the end of the month.
ETM market commentator Trevor Barsdorf said the petrol price would increase by five cents and diesel by about 15 cents.
"The rand strength late in the month is a little too late to effect a drop in the fuel prices," he said.
He added that there might only be a decrease in June.
Chris Hart, Investment Solutions economist, said there would not be a significant change.
"We are not looking for a big change," he said, estimating a 10 cent petrol increase.
Mike Schussler, T-Sec economist, said the petrol price was likely to increase by four cents, diesel by between 13 and 16 cents and paraffin by 18 cents.
He said: "This is simply as a result of an increase in oil prices and the strengthening of the rand."