(CNN) A few days after the Abqaiq and the Khurais oil facilities in Saudi Arabia were attacked, members of Congress sought information about the culprit and debated whether US military action would be necessary.

Vice President Mike Pence told a group of Republican senators at lunch Tuesday in the Capitol that the US goal is to "restore deterrence" after the attacks, which caused oil prices to fluctuate, but he did not suggest any specific retaliatory measures, according to Sen. Lindsey Graham.

"He said that the goal was to 'restore deterrence' and he left it at that," said the South Carolina Republican.

White House deputy press secretary Hogan Gidley told reporters that the Trump administration "can't say definitively" that Iran was behind the attacks, but that "in all likelihood" it was. Iran has denied responsibility for Saturday's attack.

Saudi and US investigators have determined "with very high probability" that the weekend attack was launched from a base in Iran close to the border with Iraq, according to a source familiar with the investigation. Members of Congress pointed the finger there, too -- even though Yemen's Houthi rebels have claimed responsibility -- while others called for more information.

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