Petrol, both 95 and 93, are expected to increase by 49c a litre in May, while diesel is expected to increase by between 58c/ℓ and 59c/ℓ, Energy Minister, Jeff Radebe said.

On Thursday, Radebe announced the adjustment of fuel prices for May 2018 based on current local and international factors with effect from May 2.

The increase will see petrol (both 95 - ULP and LRP) increase by 49 c/ℓ; petrol (both 93 - ULP and LRP) a 49 c/ℓ increase; diesel (0.05% Sulphur) a 59 c/ℓ increase; diesel (0.005% Sulphur)a  58 c/ℓ increase; wholesale price of Illuminating Paraffin a 52 c/ℓ increase; SMNRP of Illuminating Paraffin a 69 c/ℓ increase; and Maximum Retail Price of LPGas a 70 c/kg increase.

"South Africa’s fuel prices are adjusted on a monthly basis, informed by international and local factors. International factors include the fact that South Africa imports both crude oil and finished products at a price set at the international level, including importation costs, e.g. shipping costs," the energy department said in a statement released on Thursday.

The department listed three main reasons for the fuel price adjustment – the contribution of the Rand/US Dollar exchange rate; the increase in the prices of crude oil; and the import prices of Petroleum products.

"The Rand depreciated, on average, against the US Dollar (from 11.85 to 11.95 Rand per USD) during the period under review. The Rand’s movements were mainly influenced by global factors. The Rand went through a period of volatility in April, mainly due to concerns over the China/USA trade tariff dispute that put pressure on the currencies of emerging markets, including South Africa, the department said.

"The average Brent Crude oil price increased from $65.71 to $70.36/bl during the period under review. The US crude oil inventories dropped by 1.1-million barrels as a result of a decline of 1.3-million barrels per day in net crude imports. The crude oil market also found support in expectation that the Organisation of the Petroleum Exporting Countries (OPEC) production cuts will be sustained. OPEC and ten rival producers have curbed output by a joint 1.8-million bpd since January 2017, and pledged to do so until the end of this year.

"The international prices of petroleum products increased on average during the period under review. This was in line with the higher crude oil prices."

The department said that the fuel prices schedule for the different zones would be published on May 1.