Oil futures jumped as the market reopened Sunday night, building on last week’s surge after Israel attacked Iranian energy facilities over the weekend and underlining fears around potential disruption to Middle Eastern crude flows.

Asian shares are mixed and oil prices have climbed further as escalating Iran-Israel tensions threaten to disrupt supplies of crude.

U.S. oil prices already jumped last week, which could cause prices at the pump to rise about 20 cents a gallon in the coming weeks, according to one estimate.