The Houthi rebel faction in Yemen warned on Monday of more attacks on Saudi Arabia’s oil infrastructure, two days after strikes that interrupted much of the kingdom’s production heightened tensions between Iran and the United States and raised fears of a wider armed conflict.
United States officials have said that Iran was responsible for the attacks on Saturday, the most audacious and damaging blow to Saudi Arabia in the four and a half years of Yemen’s civil war, and have cast doubt on whether they were launched from Houthi territory in Yemen. But the American officials offered little evidence for their claims and did not address who had carried out the strikes or from where.
The Trump administration has previously blamed Iran for the actions of the Houthis, and United Nations experts say that Iran has supplied the group with drones and missiles that have greatly expanded its offensive capacity.
Iran has denied any involvement in the attacks on Saturday, and the Houthis insisted on Monday that they had carried out the strikes using drones, while threatening more, although they made no reference to whether Iranian equipment or training played a role.
A spokesman for the Houthi military, Brig. Gen. Yahya Sare’e, “warned companies and foreigners not to be present in the factories that were hit by our strikes because we may target them again at any moment,” Almasirah, the Houthi news organization, reported on Monday.
The Houthis can strike at will anywhere in Saudi Arabia, he said, and their actions against the kingdom “will expand and be more painful.”
President Trump, who has made American policy toward Iran markedly more hostile, issued a warning of his own Sunday night, saying that the United States has “reason to believe that we know the culprit” and adding that the military was “locked and loaded depending on verification.”
He did not explicitly cite Iran, but Secretary of State Mike Pompeo called on Saturday for global condemnation of Iran’s attacks, and the energy secretary, Rick Perry, used similar language on Monday at a conference in Vienna, referring to “Iran’s attack on the kingdom of Saudi Arabia.”
Saudi Arabia is leading the coalition that is fighting the Houthis in Yemen, waging a bombing campaign that has killed thousands, many of them civilians. The war there is considered the world’s greatest humanitarian crisis of recent years, displacing millions of people and leaving millions more at risk of starvation.
The Houthis claimed to have used 10 drones in the Saturday attack; American officials said that there were 17 points of impact. The rebel group has launched missile and drone attacks into Saudi territory before, but never anything on that scale, or against such vital targets, or so deep into the kingdom, some 500 miles from Yemeni territory.
The attacks on Saturday forced the shutdown of facilities at Abqaiq and Khurais, which process most of the crude oil produced by Saudi Arabia, which supplies about a tenth of the worldwide total.
Saudi Arabia and other exporters keep large oil stockpiles. Experts say it is unclear whether the Saudi equipment will be out of commission long enough to affect global oil supplies, but prices rose sharply in the immediate aftermath of the attacks.
Tensions between the United States and Iran have increased sharply since last year, when Mr. Trump withdrew from the 2015 deal limiting Iran’s nuclear program and reimposed economic sanctions against Iran. This spring, he imposed new sanctions, and Iran, which had continued to abide by the 2015 accord after the United States withdrawal, began stepping back from some of their obligations.
In May and June, several tankers were damaged in or near the Strait of Hormuz, in what American officials said were Iranian attacks. Iran has also seized several foreign ships.
On Monday, the Iranian Foreign Ministry said that a British-flagged tanker, Stena Impero, which Iran impounded while it sailed near its coast in July, will be released within days. Iran took the ship after British and Gibraltar forces seized an Iranian tanker, which was released last month after more than six weeks’ detention.