Saudi Arabia, the world's largest oil exporter, more than doubled the amount of Russian fuel oil it imported in the second quarter to feed power stations to meet summer cooling demand and free up the kingdom’s own crude for export, data showed and traders said.

The US, backed by China, submits a draft resolution to the UN Security Council aimed at imposing tougher sanctions on North Korea.

The oil price falls below $28 a barrel amid fears the lifting of Western sanctions on Iran could worsen the existing oversupply problem.

US imposes fresh sanctions on Iranian companies and individuals over a recent ballistic missile test.

A US long-range heavy bomber flew over South Korea, the US military says, days after North Korea conducted its first alleged hydrogen bomb test in defiance of international sanctions.