DUBAI — Iran warned Thursday that military action by the United States or Saudi Arabia would result in “all-out war,” as the Trump administration weighs its response after blaming Iran for crippling strikes on the kingdom’s oil infrastructure.

Secretary of State Mike Pompeo condemned the remarks, insisting that the United States and its allies were seeking a peaceful resolution, while increasing pressure on Iran to curtail its activities.

In an interview with CNN, Iranian Foreign Minister Mohammad Javad Zarif denied that Tehran was involved in the attacks and warned that retaliatory strikes risked causing significant bloodshed on Iranian soil.

“I am making a very serious statement that we don’t want to engage in a military confrontation,” Zarif said. “But we won’t blink to defend our territory.”

After a two-hour discussion with Crown Prince Mohammed bin Zayed of Abu Dhabi, Pompeo said the whole region knows that Iran was behind the attacks on Saudi Arabia.

“I think it’s abundantly clear, and there is enormous consensus in the region, that we know precisely who conducted these attacks, and it’s Iran,” Pompeo told reporters. “I didn’t hear anyone in the region who doubted that for a single moment.” On Wednesday, he met with Saudi Crown Prince Mohammed bin Salman.

“While the foreign minister of Iran is threatening an all-out war and to fight to the last American, we are here to build out a coalition aimed at achieving peace and peaceful resolution,” Pompeo added.

Regional tensions began escalating in May 2018, when President Trump pulled out of a landmark nuclear agreement between Iran and six world powers, including the United States.

In recent months, those hostilities have spilled into open violence. The Trump administration accuses Iran of using proxy forces to target Washington’s allies where they are most vulnerable: focusing on Saudi Arabia’s energy infrastructure and Western-linked ships transiting the Persian Gulf and neighboring waters.

The attacks on Saudi Arabia’s Abqaiq and Khurais oil facilities initially cut the kingdom’s production in half and caused a spike in global oil prices.

Both Washington and Riyadh have presented physical evidence and other details that they said bolstered their assertions of direct Iranian culpability.

But as tensions simmer, Trump himself has sent mixed signals over Washington’s willingness to respond with force. “There are many options. There’s the ultimate option, and there are options a lot less than that,” the president told reporters in Los Angeles, while announcing a move to increase sanctions on Iran.

Speaking to reporters at the Pentagon on Thursday, Defense Department spokesman Jonathan Hoffman said Iran was “in some way responsible” for Saturday’s attacks but stopped short of asserting that the drones and missiles that officials have said were involved in the strikes had been launched directly from Iran. “Regardless of whether this was a proxy or a direct attack, this has been a dramatic escalation from what we’ve seen in the past,” he said.

Hoffman declined to say what actions the United States might take but said the Trump administration wanted to get “back on the diplomatic path.” “Our goal is to deter conflict in the Middle East,” he said.

Col. Patrick Ryder, a spokesman for Gen. Joseph F. Dunford Jr., chairman of the Joint Chiefs of Staff, said a team of U.S. military forensic experts is continuing its work at the attack sites. He declined to say whether the Pentagon would position additional forces in the region.

Military leaders are expected to join Cabinet officials on Friday as they present Trump with options for responding to the strikes.

Pompeo, in his remarks Thursday, said more sanctions are needed to stop Iran.

“We have set about a course of action to deny Iran the capacity and wealth to prevent them from conducting their terror campaigns, and you can see from the events of last week there is still more work to do,” he said.

In a news conference Wednesday, a spokesman for the Saudi military, Col. Turki al-Malki, said Saturday’s attack on the Abqaiq oil processing plant in eastern Saudi Arabia had involved 18 unmanned aerial vehicles. Seven cruise missiles, he added, were fired at a facility in Khurais, the site of one of the kingdom’s largest oil fields.

These strikes were, he said, “unquestionably sponsored by Iran.”

Saudi officials have not determined the location from where the weapons were launched, though Malki declared, “This attack did not originate from Yemen, despite Iran’s best effort to make it appear so.

“Their collaboration with their proxy in the region to create this false narrative is clear,” he said, basing the assertion in part on the purported range of the weapons recovered, which he said could not have traveled from territory in Yemen held by the Iran-aligned Houthi rebel movement.

The Houthis have been fighting a nearly five-year war against a Saudi-led coalition in Yemen.

A U.S. defense official, who spoke on the condition of anonymity to address internal deliberations, said Saudi Arabia had been under “pretty much daily” attacks from Yemen since May. According to the Saudi government, Houthi rebels have fired more than 66,000 rockets and artillery pieces into Saudi Arabia since the beginning of their war with the kingdom in 2015. Saudi officials say those attacks have killed more than 100 civilians.

While the Saudi military has defenses directed at those threats from the south, the defense official said, “the bottom line is that they don’t have enough to protect in every direction or every asset.”

Now, given the recent attacks, the official said the Trump administration would “have to make a decision about whether or not it’s going to assist Saudi Arabia in its defense.”

If Trump did approve such a step, the Pentagon would be likely to position missile defense batteries, including Patriot systems; additional fighter jets; and additional surveillance assets in or around Saudi Arabia. Such a move would also involve sending troops to operate that weaponry.

Consideration of those items was first reported by the Wall Street Journal.

Tehran is able to rely in varying degrees on a web of proxy forces from Yemen to Lebanon and Iraq, raising the stakes of any U.S. confrontation with Iran.

In Iran, officials have described the growing hostility as a direct response to U.S. sanctions, which are crippling Iran’s economy. Zarif said sanctions relief “could change Tehran’s calculations, opening the possibility for talks.”

The Houthis also reiterated their claim that they carried out the attacks with domestically designed weaponry.

“Our forces have reached a high level of efficiency and ability. They can manufacture various types of unmanned aerial vehicles in record time,” Houthi military spokesman Yahya Saree said in a news conference late Wednesday.

The Houthi claim has been met with skepticism from experts and government officials, especially in light of the nature of war-torn Yemen’s economy and industrial capacity.

“The Houthis . . . announced that they launched this attack. That lacks credibility,” French Foreign Minister Jean-Yves Le Drian told a French TV station on Thursday. He also called the strikes an “act of war,” although he declined to speculate who was behind them.

The U.S. government has issued visas permitting Iranian President Hassan Rouhani and Zarif to travel to New York for the United Nations annual meeting next week. Rouhani was contemplating skipping the visit if the visas were not issued promptly, Iranian state media reported Wednesday. On Thursday, Alireza Miryousefi,a spokesman for the Iranian mission to the United Nations, said the visas had been granted.

The United States this summer blackballed Zarif from coming to the United States as part of its sanctions campaign aiming to get Iran to renegotiate the 2015 nuclear deal. But as the “host” nation of U.N. headquarters, the United States has agreed to issue visas to diplomats traveling to New York on official U.N. business.

Loveluck reported from Baghdad. Asser Khattab in Beirut and Missy Ryan and Carol Morello in Washington contributed to this report.