Oil gains as investors cautious over Iran-Oman talks

"Until we see sustained, verifiable increases in volumes, the market will continue to price in a degree of supply risk," Waterer added.

Gulf countries' crude oil and condensate exports were largely steady in July and remained about 40% below pre-war levels, shipping data showed.

Iran has warned Gulf states that any new U.S. attack on its territory would trigger retaliation against critical energy infrastructure across the region, according to five sources, as Tehran seeks to raise the cost of military action by threatening Washington's closest regional allies.

Yemen's Iran-aligned Houthis said on Wednesday they had launched a missile attack on a Saudi oil tanker off the coast of the kingdom's Red Sea port city of Yanbu and another missile attack on a Saudi oil tanker in the nearby Gulf of Aden. There was no confirmation from Saudi Arabia on either incident.