Saudi Arabia said Tuesday it is scaling back its military intervention in Yemen, after more than three weeks of punishing airstrikes failed to drive back the Shiite rebels that have plunged the Arabian Peninsula nation into chaos.

At a news conference in the Saudi capital, Brig. Gen. Ahmed Asiri announced that the coalition led by Saudi Arabia would begin a new operation in Yemen that focuses on addressing a worsening humanitarian crisis, combating terrorism and finding a political solution to the fighting.

He maintained that the initial phase of the campaign had achieved its military objectives by successfully eliminating threats to Saudi Arabia’s security, including the destruction of the rebels’ supply of missiles and heavy weapons.

The announcement marks an end to what has been the largest military operation ever conducted by Washington’s Persian Gulf ally. Dubbed “Decisive Storm,” the campaign is part of a more aggressive regional policy assumed by Riyadh that in part has been motivated by frustration over a fledgling U.S. rapprochement with Iran.

But the change in direction comes amid rising doubts among Riyadh’s allies over the objectives and fallout of the conflict, which has further destabilized Yemen, helping radical groups such as al-Qaeda expand their influence there.

A man walks past a car damaged by a recent air strike in Sanaa on April 21. (Mohamed Al-Sayaghi/Reuters)

The coalition, consisting of primarily Sunni Arab countries, will still target the rebels, called Houthis, Asiri said. Riyadh considers them to be a proxy for its foremost nemesis, Shiite Iran. But Asiri did not specify what that targeting might entail.

The coalition airstrikes that began on March 26 have killed nearly 1,000 people, more than 300 of them civilians. In addition, a naval and air blockade has choked off supplies of food and fuel to the impoverished country of over 25 million people, which aid agencies say has worsened Yemen’s already dire humanitarian situation.

Even after the Saudi announcement, the roar of planes and the booms of what were apparently antiaircraft weapons could still be heard in Sanaa, residents said. The capital has been subjected to intense bombardment by the coalition, including an airstrike on an arms depot Monday that killed dozens of people, including civilians.

Rumored talks with Houthis

Saudi Arabia, a Sunni powerhouse, has grown increasingly alarmed over the rising influence of Iran in such Arab countries as Iraq and Syria. Further, its government views a possible nuclear accord with Washington as a potential green light for Tehran’s continued expansion in the region.

It is unclear how the coalition intends to deal with the Houthi rebels, who still control vast amounts of Yemeni territory they have captured in assaults over the past year.

Some Houthi officials and their supporters were defiant after the Saudi disclosure.

“This announcement of a halt to this operation is nothing but a shameful defeat for Saudi,” said Mohammed Meftah, a prominent pro-Houthi politician who lives in Sanaa. He added that Riyadh would have to pay billions of dollars in reparations for the damage caused by the airstrikes, saying that Saudi Arabia bears “criminal responsibility.”

Before the Saudi announcement, however, rumors had swirled that intermediaries were helping the Houthis and officials in Riyadh set the terms for a possible cease-fire and peace talks.

Analysts said that the Houthi advances crossed a red line for Saudi Arabia, which sees Yemen as part of its back yard. Iran’s perceived attempts to extend its influence there were unacceptable to Riyadh, they said.

Abdul-Ghani al-Iryani, a Yemeni analyst who lives in Sanaa, expressed doubt that the Saudi-led coalition would succeed in returning Yemen’s president, Abed Rabbo Mansour Hadi, to power. After the Houthis toppled his government in February, Hadi fled to Saudi Arabia, where he and a number of officials opposed to the rebels have tried to plot their return to Yemen.

“Hadi’s rule has come to an end,” Iryani said.

The coalition’s initial war aim of driving the rebels out of major urban centers, including Sanaa, the capital, has not been achieved. The rebels control most of northern Yemen, and they still threaten to take the southern port city of Aden, which has been decimated by the fighting.

Concerns about airstrikes

A senior official from one of the Gulf Cooperation Council countries backing the Saudi-led operation said the objective of the airstrikes, and collateral damage, was “becoming an issue,” especially at the United Nations. “All of them want to see an end to this war,” said the official, who spoke on the condition of anonymity.

“The objective is not to create misery for the Yemeni people, but to make sure the political process is intact,” the official said. “We don’t want to see a humanitarian crisis in Yemen, and it was getting very bad.”

While the Houthis have remained publicly defiant, the official cited signs in recent days that the rebels’ allies — forces loyal to former Yemeni president Ali Abdullah Saleh — had begun to fracture and draw away from the fight. “The Houthis were hurt” by the strikes, “but not as much as Saleh,” the official said. “Now is the time for a political solution.”

In Washington, a spokesman for the National Security Council, Alistair Baskey, said that “the United States welcomes” the Saudi announcement.

“We continue to support the resumption of a U.N.-facilitated political process and the facilitation of humanitarian assistance,” he said.

U.S. officials have grown uneasy about the coalition’s objectives and the shift in focus away from Yemen-based al-Qaeda in the Arabian Peninsula, which has taken advantage of the chaotic situation to expand its activities.

Defense Secretary Ashton B. Carter has had several telephone calls in recent days with his Saudi counterpart, Mohammad bin Salman, and Gen. Lloyd J. Austin III, the head of U.S. Central Command, spent Thursday in Riyadh to consult “with the Saudi leadership on their campaign plan,” said Gen. Martin E. Dempsey, chairman of the Joint Chiefs of Staff.

Naylor reported from Beirut. Karen DeYoung in Washington contributed to this report.

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