After weeks of attacks by Yemen’s Houthi militia on Saudi ships, airports and oil facilities, Saudi Arabia appears to be preparing for a renewed war against the group, analysts say, potentially deepening the turmoil in the Middle East.

It is unclear what Saudi Arabia’s goals would be if it were to go back to full-blown war with the Houthis. But it could open a new front in the U.S. war with Iran — the Houthis’ primary backer.

When the kingdom last embarked on a bombing campaign against the Houthis, in 2015, it turned into a decade-long quagmire that entrenched the group’s rule in northern Yemen and resulted in the deaths of hundreds of thousands of Yemenis from violence, hunger and disease.

Few observers or officials believe there is a realistic path to routing the militia entirely. Instead, Saudi Arabia could aim to weaken the group and pressure it to negotiate a resolution to Yemen’s civil war that is more favorable to the kingdom and its Yemeni allies, analysts say.

Channels that were kept open for years between the two sides appear to have broken down. “I am not seeing a political offramp at this point,” said Mohammed al-Basha, a Yemen-focused political analyst based in Washington. “War is coming.”

Earlier this week, the Houthis claimed responsibility for a ballistic missile attack on a Saudi oil tanker as well as two attacks on Saudi-backed forces inside Yemen, with the group’s military spokesman, Yahya Saree, promising to confront any escalation with “stronger and more severe strikes.”

A Saudi official, speaking on condition of anonymity in line with government protocol, said that the kingdom prefers peace, but is ready for war with the Houthis, and will protect itself by any means necessary.

If the Houthis continue to escalate their attacks, he added, the kingdom would be willing to conduct airstrikes to support the Yemeni government — effectively, a motley coalition of anti-Houthi forces — in its battle against the militia.

The last Saudi intervention in Yemen was an effort to restore the internationally-recognized government, which the Houthis had ousted from the Yemeni capital, Sanaa, with Iranian support. The fighting brought the country to the brink of famine and ultimately failed to rout the Houthis.

After a truce in 2022, the Houthis emerged with the conviction that they had won. Saudi officials turned to dialogue, hoping to contain the militia on their southern border and garner influence over it.

That approach appeared to work, until the U.S.-Israeli war against Iran turned into a regionwide conflagration, shifting the Houthis’ calculus.

Yemeni analysts say the militia is acting in part to aid Iran, but that it is also pushing to consolidate its power and secure access to Yemen’s oil resources after years of political stalemate. The group is increasingly describing itself as a legitimate state, and demanding to be treated as such.

Tensions between the kingdom and the militia began to escalate last month, after the Houthis accused Saudi Arabia of bombing Yemen’s main international airport to prevent an Iranian plane from landing, which the kingdom denied. The Houthis then declared a maritime blockade on Saudi ships in the Red Sea.

Since then, Saudi Arabia has carried out limited airstrikes in Yemen, and the Houthis have launched missile and drone attacks inside Saudi Arabia, in addition to attacking Saudi ships in the Red Sea.

Those attacks have put pressure on global energy markets, in line with Iran’s own interests. Saudi Arabia, the world’s largest oil exporter, typically ships its oil through the Strait of Hormuz, a narrow waterway connecting the Persian Gulf to the world’s oceans that Iran has effectively closed since the Iran war began. The kingdom now relies on the Red Sea to export most of its oil.

Inside Yemen, clashes between the Houthis and the Saudi-backed Yemeni government have escalated sharply in recent weeks.

“Yemen today faces a more serious risk of return to large-scale conflict than at any point since the 2022 U.N.-mediated truce,” the United Nations envoy to Yemen, Hans Grundberg, warned in a briefing to the U.N. Security Council on Aug. 13.

The Houthis say that their attacks are pre-emptive, accusing the Saudi and Yemeni governments of amassing forces in preparation for a ground offensive against them.

Mohammed al-Bukhaiti, a Houthi political official, said in an interview that the militia was already “practically in a state of war with Saudi Arabia.”

The Houthis are “keen to keep our options open” and hope to prevent “an expansion of the conflict,” he said. But if full-scale war breaks out, they will “destroy all of Saudi Arabia’s oil and vital facilities,” he added, “just as it did to Yemen.”

He accused Saudi Arabia of imposing “a blockade on Yemen by force of arms and preventing food, medicine and basic necessities from reaching the Yemeni people.”

Saudi officials deny that allegation. They accuse the Houthis of trying to evade a U.N. inspection regime and other safeguards meant to prevent the militia from obtaining weaponry and funding.

Earlier this month, Saudi Arabia’s ambassador to the United States, Princess Reema bint Bandar, conveyed the kingdom’s concerns to Washington. Accompanying the Yemeni ambassador, Jamila Rajaa, she met with members of Congress to emphasize the threat posed by the Houthis.

The ambassadors argued that there was a need to push back against the militia and encouraged the United States to back that effort, according to a U.S. official and a Yemeni official familiar with the meetings. They spoke on the condition of anonymity to discuss sensitive diplomacy.

It is unclear what that backing could look like, but in a subsequent opinion column in The Wall Street Journal, Ms. Rajaa called on the United States to “sustain and enhance support” for the Yemeni military, increase humanitarian assistance to Yemen and expand its designation of the Houthis as a foreign terrorist organization.

Analysts say that there are now signs of a broader military buildup on both sides.

Ahmed Nagi, a senior analyst for Yemen at the International Crisis Group, said that Saudi Arabia has improved military coordination between different anti-Houthi factions. It is also providing those forces with advanced weaponry, which “has never been the case in the past,” Mr. Nagi added.

In an interview with a Saudi newspaper published last week, Abdullah al-Alimi, a member of the Yemeni government’s presidential leadership council, praised Saudi Arabia’s role in providing training and other assistance to Yemeni government forces.

It has become “inevitable,” he said, that the Saudi-backed Yemeni government will retake Sanaa from the Houthis.

For Saudi Arabia, there are many reasons to avoid war: Another battle with the Houthis could drain its finances and defense stockpiles, and it could endanger the crown prince’s plans to turn the kingdom into a business and tourism hub.

The Houthis, though, are “not ready to negotiate” and are pushing for political concessions in Yemen, while also acting to aid their main backer, Iran, Mr. Nagi said.

Experts and diplomats fear that any escalation will increase the suffering of tens of millions of people in Yemen, which is already engulfed in one of the world’s worst humanitarian crises.

“No party controls where escalation leads,” Mr. Grundberg said during his U.N. briefing. “The only certainty is that the Yemeni people will pay the price.”

Shuaib Almosawa contributed reporting from Sanaa, Yemen, Saeed Al-Batati from al-Mukalla, Yemen, Eric Schmitt from Washington, Adam Rasgon from Tel Aviv and Edward Wong from Kutaisi, Georgia.