US calls on OPEC+ to raise crude oil output further

"We are engaging with relevant OPEC+ members on the importance of competitive markets in setting prices," US national security adviser, Jake Sullivan, said in a statement seen by CNBC.

"Competitive energy markets will ensure reliable and stable energy supplies, and OPEC+ must do more to support the recovery."

Also on Wednesday, in a letter sent to the head of Federal Trade Commission, Brian Deese, the head of the US National Economic Council, asked the FTC to consider "monitoring the US gasoline market and addressing any illegal conduct" that might be impacting on gasoline prices.

On 18 July, OPEC+ members, which included countries the cartel plus the likes of Kazhakstan and Russia, agreed to raise their combined production by 400,000 barrels a day, each month, from August.

At the time of the decision, OPEC+ was sitting on 5.8m b/d of capacity in a bid to prop up crude oil prices.

Regular gasoline prices across the US had hit $3.185 per gallon the day before, which was up sharply on the year ago level of $2.174.