A drone attack launched by Yemen's Houthi group on an oilfield in eastern Saudi Arabia on Aug. 17 caused a fire at a gas plant but had no impact on oil production, state-run oil company Saudi Aramco said.
The report by OPEC also said oil inventories in developed economies rose in June, suggesting a trend that could raise the group's concern over a possible oil glut.
The Iranian vessel was seized on July 4, with Iran accused of violating sanctions by shipping oil to Syria.
Oil prices fell on Aug. 12 amid worries about an economic slowdown and the U.S.-China trade war, which have led to a cut in the outlook for global oil demand
Saudi Aramco reported a 12% fall in half-year net profit on Aug. 12, yet remained the world's most profitable company, while India's Reliance Industries said Aramco is looking to buy into its refining and petrochemicals business.
Iraq's oil ministry said on Aug. 10 it was still in talks with Exxon Mobil Corp. over a major deal to improve the country's southern oil infrastructure.
Mermaid Maritime Public Co. Ltd. said that its Middle East and South East Asian business units have recently been awarded subsea contracts with a combined total estimated potential contract value of $7.4 million on Aug. 9.