United States Senator, Ron Wyden, chairman of the Senate Committee on Energy asked the Department of Justice (DOJ) to participate in the investigation of the European Commission (EC) in connection with the alleged oil price manipulation in Europe, according to a report from Simon Falush and Timothy Gardner of Reuters.

Ron Wyden

Sen. Ron Wyden, chairman of the Senate Committee on Energy and Natural Resources asked the DOJ to find out if the alleged price manipulation increased the prices of fuel for consumers in the United States.

“Efforts to manipulate the European oil indices, if proven, may have already impacted U.S. consumers and businesses, because of the interrelationships among world oil markets and hedging practices,” according to Sen. Wyden in his letter to Attorney General Eric Holder.

The European Commission expanded their inquiry on the issue from three major oil companies to small-niche trading house. Authorities visited Argos Energies, trading house in Netherlands and requested to submit information. The company is a wholesaler and provides logistics services for oil products in the Western European Energy market.

EC authorities visited Argos Energies the same day when they raided BP plc (NYSE:BP) (LON:BP), Royal Dutch Shell plc (NYSE:RDS.A) (NYSE:RDS.B), Statoil ASA (NYSE:STO), and Platts pricing agency in London. Some sources cited that inspectors were seen at the premises of Argos Energies on Friday, which was the last day of its inquiry.

The European Commission’s action is another huge cross-border investigation following the probe on the manipulation of the Libor benchmark interest rates. Sen. Wyden normally ask authorities to look into issues affecting fuel prices.

According to Reuters, the United Stated Commodity Trading Commission (CFTC) and Federal Trade Commission (FTC) declined to comment regarding any coordination or involvement with the EC regarding its on-going investigation on the alleged oil price manipulation. A spokesperson for the DOJ said the agency is reviewing Wyden’s letter, but refused to comment whether it will conduct an investigation on the issue.

The EC also sent a notice to Neste Oil Corporation (HEL:NES1V) to submit information, although it clarified that the company is not under investigation. Matti Lehmus, executive vice president, Oil Products and Renewables said, “We will naturally cooperate with this request and provide the information requested to assist the European Commission in its investigation.”

Pannonia Ethanol, Hungarian company and a new entrant in the European energy market admitted complaining with authorities regarding access to Platts market-on-close (MOC) system.

On the other hand, Christophe de Margerie, CEO of Total SA (NYSE:TOT) said that the company has nothing to do with the recent investigation of the European Commission. “No, we haven’t sent any letter. I’ve learnt about this through the press and news agencies. I’d be very surprised if some of the cited companies were involved in price manipulation,” replied Margerie when reported asked him if the company was one of the complainants. A year ago, Total SA (NYSE:TOT) asked regulators to inquire about the process of determining oil prices, but not this year.

Thomson Reuters and Platts compete in providing news and information to the oil market.