U.S. President Donald Trump said on Monday that his country is "locked and loaded" for a potential response to the attack on Saudi Arabia's oil facilities.
"There is reason to believe that we know the culprit. We are locked and loaded depending on verification, but are waiting to hear from the Kingdom [Saudi Arabia] as to who they believe was the cause of this attack, and under what terms we would proceed!" Trump said on Twitter.
U.S President also authorized the use of the emergency oil stockpile, to ensure stable supplies after the attack, which has shut 5% of world oil 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 said.
Earlier in the day, a senior U.S. official told reporters that evidence from the attack, which hit the world's biggest oil-processing facility, indicated Iran was behind it, instead of the Yemeni Houthi group.
Secretary of State Mike Pompeo had also blamed Tehran for coordinating the drones that hit two oil facilities in Saudi Arabia.
"Tehran is behind nearly 100 attacks on Saudi Arabia. Iran has launched an unprecedented attack, on the world's energy supply," he said on Twitter.
Iranian Foreign Ministry spokesman Abbas Mousavi, however, dismissed the U.S. allegations, describing them as "irresponsible "and "pointless".
On Sept. 14, the official Saudi Press Agency reported the blazes at the Abqaiq and Khurais facilities. Abqaiq is home to the state-owned, Saudi Aramco's largest oil processing plant. A day later, Saudi Arabia announced halting oil production temporarily, from these oil facilities.
Although no group has yet, specifically claimed responsibility for the attacks, the Houthi rebels in Yemen, fighting against the Saudi-led coalition, said they have carried out similar attacks in the past.
The Iran-backed Houthis, whose medium and long-range ballistic missiles are usually intercepted and neutralized by the Saudi air defense system, have targeted certain strategic locations of Saudi Arabia with armed drones.
Yemen has remained wracked by violence since 2014, when the Iran-aligned Houthi group overran much of the country, including the capital Sanaa.
The conflict escalated the following year, when Saudi Arabia and its Arab allies launched a massive air campaign aimed at rolling back Houthi gains to support the country's pro-Saudi government.
More than 70,000 people have been killed in the raging conflict since 2016, according to the UN estimates.
In addition, Saudi Arabia's airstrikes seeking to support the government have led to death of scores of civilians in the war-ravaged country since 2015.
