A team of U.S. military forensics specialists is already on the ground to gather evidence from the sites of the attacks, Gen. Joseph Dunford, the chairman of the Joint Chiefs of Staff, told reporters traveling with him in London.
The U.S. is gathering "compelling forensic evidence" from the debris of the cruise missiles and drones at the two oil facilities attacked this weekend, said a U.S. official. That evidence "will provide a compelling case of where they came from," the official said.
A third U.S. official had previously told ABC News that a cruise missile and drone targeting the two facilities had been found mostly intact.
President Donald Trump and his top advisers have said that Iran was likely responsible for the attack, but the president said he was not in a rush to respond as the U.S. continues to assess the strike.
Instead, U.S. officials told ABC News that the president wants Saudi Arabia to point the finger at Iran -- a move the kingdom has yet to take. Saudi Arabia's Energy Minister said on Tuesday that it did not yet know who carried out the attack, although they have determined the weapons themselves were Iranian.
Still, the region remains on edge, weighing the gravity of a potential attack on one country by another and what kind of retaliation may come next.
The U.S. investigators on site have been sifting through a significant amount of debris from the drones and missiles launched on Saturday. An American official told ABC News that the U.S. believes some 20 drones and nearly a dozen cruise missiles were used in the attacks.
The U.S. is working to declassify intelligence that administration officials hope will prove to the public that Iran was behind the attack.
Dunford expressed confidence that the Houthi rebels in Yemen were not responsible for the attack, as the group had originally claimed.
"Without prejudging intelligence, this looked like a very complex, precise attack, not consistent with previous Houthi attacks," Dunford said, according to reporters traveling with him. "We can say that now -- that this attack was not consistent with previous Houthi attacks."
In Jeddah, Pompeo will meet with Saudi Crown Prince Mohammed bin Salman to "coordinate efforts to counter Iranian aggression in the region," according to his spokesperson Morgan Ortagus. Pompeo will then travel on to the United Arab Emirates to meet the country's Crown Prince Mohammed bin Zayed.
Trump said the U.S. was "locked and loaded" on Sunday night, but was waiting for the Saudis to verify Iran's culpability and provide guidance on "under what terms we would proceed!"
"The president has made it clear he is not looking to go to war," Dunford said Tuesday. "Having said that, what we saw was an unacceptable act of aggression. There are a number of ways to deal with that."
In a speech at the Heritage Foundation in Washington on Tuesday, Vice President Mike Pence echoed that sentiment, but added that the U.S. is "prepared" to respond.
"We're locked and loaded," Pence said, echoing the president. "We're ready to defend our interests and our allies in the region, make no mistake about it."
Despite the high tensions in the aftermath of the Saudi oil facilities attack, the Trump administration doesn't fear a wider conflict and believes Iran will "come back down."
"Iran has a long history of testing its strength. But they never climb too high up the escalation ladder. At a certain point, when the world says enough, they come back down," a senior administration official told ABC News on Tuesday.