US heating oil prices rose more than 7% to about $4.19 per gallon after Iran-backed Houthi militants claimed an attack on Saudi Arabia’s Jazan refinery near the Red Sea. Saudi authorities said a fire linked to the incident was extinguished early Sunday, but gave no further details. The flare-up intensified concerns in an already tight global diesel market, where supply has been squeezed by disruptions to shipping through the Strait of Hormuz and by Russia’s fuel export restrictions. Refining capacity is also under pressure as demand for fuel continues to outstrip supply. In the United States, refiners are processing crude at the highest seasonal rate since 2018 even though capacity has fallen by nearly 600,000 barrels per day over the same period. Meanwhile, Iran and Oman have not yet finalized a deal to reopen Hormuz. Iran said an agreement was "very close," but said the US must lift its blockade and provide compensation before the waterway reopens.