US has issued satellite images and cited intelligence to back its claim that Iran was behind the drone attacks on two Saudi oil facilities on Saturday.
The attacks were claimed by Houthi rebels in Yemen.
According to the BBC, unnamed US officials told American and international media that the direction and extent of the attacks cast doubt on Houthi involvement.
One official said there were 19 points of impact on the targets and the attacks had come from a west-north-west direction – not Houthi-controlled territory in Yemen, which lies to the south-west of the Saudi oil facilities.
Iran has denied involvement in the attacks that targeted Abqaiq, the site of the largest oil processing plant run by the Saudi state oil company, Aramco, and the Khurais oilfield.
The attacks shutting 5 per cent of global crude output caused the biggest surge in oil prices since 1991. The price rose 20 per cent today but fell back later.
The international benchmark used by traders, Brent crude, jumped to 71.95 Dollar a barrel at one point. The intra-day jump was the biggest since the 1991 Iraqi invasion of Kuwait that prompted the Gulf War.