South Africa’s Gold Fields expects its costs to increase as the Iran war has driven the prices of inputs such as fuel and explosives higher, it said, Reuters reports.

“The forecast impact of this, assuming an oil price of $100 per barrel, is between $40 to $50 per ounce on a portfolio level,” it said in a quarterly update.

Gold Fields did not change its cost guidance for the year, however, saying measures, such as more fuel-efficient, high-capacity haulage systems at its mines, should contain costs.