RIYADH: US President Donald Trump on Monday said American forces are ready to strike back at whoever were behind the recent attacks on Saudi Arabias oil refinery and oil field. "There is reason to believe that we know the culprit, are locked and loaded depending on verification, but are waiting to hear from the Kingdom as to who they believe was the cause of this attack, and under what terms we would proceed!", he said in a tweet. Saudi Arabia oil supply was attacked. There is reason to believe that we know the culprit, are locked and loaded depending on verification, but are waiting to hear from the Kingdom as to who they believe was the cause of this attack, and under what terms we would proceed! — Donald J. Trump (@realDonaldTrump) September 15, 2019 Trump also said he had also authorized the use of the U.S. emergency oil stockpile to ensure stable supplies after the attack, which shut 5% of world production. “Based on the attack on Saudi Arabia, which may have an impact on oil prices, I have authorized the release of oil from the Strategic Petroleum Reserve, if needed, in a to-be-determined amount sufficient to keep the markets well-supplied,” he tweeted, “I have also informed all appropriate agencies to expedite approvals of the oil pipelines currently in the permitting process in Texas and various other States.” ....sufficient to keep the markets well-supplied. I have also informed all appropriate agencies to expedite approvals of the oil pipelines currently in the permitting process in Texas and various other States. — Donald J. Trump (@realDonaldTrump) September 15, 2019 Oil prices surged more than 15% at the open on Sunday on worries over global supply and soaring tensions in the Middle East. On Sunday, a senior U.S. official told reporters that evidence from the attack, which hit the worlds biggest oil-processing facility, indicated Iran was behind it, instead of the Yemeni Houthi group that had claimed responsibility. — with Reuters