Standard & Poor's Global Commodity Insights said that Saudi Aramco Oil Company began, on Monday, trading in American crude oil, which is used to determine the price of global benchmark Brent crude oil, in a process managed by the platform responsible for disseminating energy information.

Aramco, the Saudi state oil company and the largest oil company in the world, is expanding its business activity.

Trade sources told Reuters that Aramco on Monday sold a shipment of US West Texas Intermediate Midland crude to Total during Platts’ “market at close” process, known as the Platts window. Last Thursday, Aramco sold another shipment of this American crude.

Joel Hanley, global director of crude and fuel oil markets at Standard & Poor's Global, said in an email that these were Aramco's first deals related to WTI Midland crude in the market at close process.

He added that Aramco purchased a shipment of North Sea crude (DUC) in December, its first deal since joining the operation.

US Midland WTI is one of six types of crude oil evaluated by Platts that can determine the value of dated Brent crude, part of the broader Brent complex used to price more than three-quarters of the world's traded oil.