President Trump on Sunday said that the U.S. would be tapping into its Strategic Petroleum Reserve "if needed" in the wake of attacks on oil sites in Saudi Arabia. "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," the president said in a series of tweets.

The attack over the weekend could disrupt an estimated 5.7 million barrels of oil per day, or more than 5% of the world's daily supply. Oil prices surged more than 10% late Sunday.

Mr. Trump's announcement came after a National Security Council meeting with Secretary of State Mike Pompeo and Defense Secretary Mark Esper at the White House. The president then tweeted "Saudi Arabia oil supply was attacked" and the U.S. is "locked and loaded" pending verification from Saudi Arabia as to who was behind the attack.

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

The decision also comes one day after a drone attack hit the heart of Saudi Arabia's oil industry. The Trump administration has pinned the blame on Iran.

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Iran pushed back hard, calling U.S. accusations "maximum lies" and threatening that its forces could strike U.S. military bases in the Middle East. Pompeo issued two tweets blaming Tehran — without proof — despite Yemen's Houthi rebels claiming responsibility.

Lawmakers, like Representative Liz Cheney of Wyoming and Senator Adam Schiff of California, backed up Pompeo's claims. "I think Secretary Pompeo's statements yesterday were absolutely right," Cheney said. "I think it's very clear this was the Iranians."

"I think it's safe to say that the Houthis don't have the capability to do a strike like this without Iranian assistance," Schiff added.

Prior to Mr. Trump's announcement, the Energy Department said it stood "ready" to tap into the strategic petroleum oil reserves if necessary to offset any disruptions.