The attacks came in retaliation for the Saudi-led coalition's continued aggression on the Arabian Peninsula country.
The exposure of the Abqaiq facility to sabotage or attack has always been a concern not only of successive Saudi governments but U.S. administrations as well.
"These unacceptable actions are cause for alarm", Pelosi said in a statement accusing Trump of turning "a blind eye" to Saudi violence against innocent Yemenis, human rights abuses and the murder of journalist Jamal Khashoggi.
'Well, it is hard for the United States to explain why its state of the art equipment was not able to intercept these weapons.
"Congress will perform our job to maintain the Constitution protect our national safety and safeguard the American men and women".
A Saudi-led coalition has battled the Houthis in Yemen since March 2015, a conflict that has killed tens of thousands of people and sparked what the United Nations describes as the world's worst humanitarian crisis.
Speaking to CNN on September 22, Saudi Foreign Minister Adel al-Jubeir made a distinction between the current assessment of Iranian culpability over the weapons' origins and a finding that the bombings of the Abqaiq and Khurais oil facilities were staged from Iran.
During his speech, Rouhani described the sanctions as "economic terrorism" but said the "revolutionary people" of Iran were not intimidated by what he described as "threats".
Esper and Dunford declined to discuss any potential ship movements to the region, although a number of U.S. Navy vessels are nearby.
The United Nations General Assembly will be held this week, with leaders from around the world gathering in New York City.
"Nonetheless to launch an assault out of your territory, if that is so, places us in a undeniable category... this is able to be thought of as an act of conflict".
The United States has also sent mixed signals.
Tensions between Iran and the United States and its allies have threatened to boil over since May a year ago when President Donald Trump unilaterally withdrew from a 2015 nuclear deal and later began reimposing sanctions in a campaign of "maximum pressure". The U.N., Gulf Arab nations and the US accuse Iran of supplying arms to the Houthis, something Tehran denies.
Officials said 110 contractors evacuated the site after the attack and there were no injuries.
NetBlocks, an organisation that monitors internet connectivity, earlier reported "intermittent disruptions" to some internet services in Iran starting on Friday evening.
The team said the effect was limited, affecting only particular suppliers, and the reason was uncertain.
"I don't know why anybody listens to the Iranian Foreign Minister".