Donald Trump has said he will “substantially increase” sanctions on Iran.
The president’s announcement comes two days after he told reporters it was “looking like” Iran was behind the attacks on Saudi Arabia’s oil facilities, but he insisted he does not want war.
The Saudi government is preparing to present “material evidence” proving Iranian involvement in the weekend’s attack.
The Saudi Defence Ministry are expected to present Iranian weapons to substantiate claims that Iran was responsible for the attack, as US Secretary of State Mike Pompeo lands in the Saudi city Jeddah.
Iran has rejected claims it was to blame for Saturday’s drone attacks, which damaged the world’s biggest crude processing plant and triggered the largest jump in crude prices in decades.
Global prices surged nearly 20% following the bombing of two oil plants, before dropping about 10% within 24 hours when markets calmed in reaction to Mr Trump’s suggestion that America’s stockpile could be used if required.
Yemen’s Houthi rebels, who are backed by Iran, say they are responsible and have warned of more strikes.
However, Saudi Arabia and the US have accused Iran of being behind the attacks on the Abqaiq facility and the Khurais oil field in the early hours of Saturday.
Iran and Saudi Arabia are locked in a long-standing power struggle in the region.
Saudi Arabia is leading a coalition in a war against the Houthi rebels in Yemen. It is often described as a proxy war between Saudi Arabia and Iran.