WASHINGTON − President Donald Trump said the U.S. will end airstrikes on Houthi militants in Yemen effective immediately.

"We will stop the bombings," Trump announced from the Oval Office.

Trump ordered Secretary of State Marco Rubio, who he tapped as his acting national security adviser last week, to pass on the message to the Iran-backed militant group.

The Trump administration began a costly bombing campaign on March 15 in response to Houthi attacks on commercial shippers in the Red Sea.

Ever since, the U.S. has launched continuous strikes through “Operation Rough Rider." Former President Joe Biden also launched hundreds of strikes on the Yemeni militant group in an attempt to repel its attacks on international shipping in the Red Sea.

The Houthis - known officially as Ansar Allah - say their attacks are in retaliation for Israel’s ongoing siege of Gaza and U.S. military support. The group is allied with Hamas, and both are part of the “Axis of Resistance,” a loose allegiance of Iran-backed militant groups.

Israel unleashed a bombing campaign and ground invasion of Gaza after Hamas’ Oct. 7, 2023, attack on Israel’s border communities.

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On May 4, the Houthis fired a ballistic missile into Israel that landed near Ben Gurion Airport. Israel launched heavy strikes on Yemen’s Sana’a Airport and other populated areas in response.

Trump announced the end to U.S. airstrikes as he met with Canadian Prime Minister Mark Carney at the White House. He said Houthi rebels had informed the U.S. the evening before that they were ready to stand down. Trump said he would honor their request.

"They have capitulated, but more importantly ... we will take their word," he said. "They say they will not be blowing up ships anymore."

Rubio said after Trump invited him address journalists: "If it's going to stop, then we can stop."

Trump declined to say later in the meeting how he learned that the Houthis were waving the white flag, attributing the information to a "very good source."

In a statement earlier in the day, in response to Israel's strikes, the rebels indicated they were not backing down.

"The operations of our armed forces will continue and the support by Yemen to Palestine will only end with the end of the aggression and siege against Gaza," the group said, according to Al Masirah TV.

Oman announced U.S.-Houthi ceasefire

State Department spokeswoman Tammy Bruce pointed to a post on social media, reshared by Trump's special envoy to the Middle East, from Omani Foreign Minister Sayyid Badr Albusaidi that said a ceasefire had been brokered.

"In the future, neither side will target the other, including American vessels, in the Red Sea and Bab al-Mandab Strait, ensuring freedom of navigation and the smooth flow of international commercial shipping," Albusaidi said.

A quarter-billion dollars in Yemen airstrikes

Details of an attack on Houthis targets were at the center of the Signalgate controversy. Defense Secretary Pete Hegseth shared sensitive details about the timing of the strikes on the commercial messaging app. The chat inadvertently included journalist.

The U.S. has launched more than 1,000 strikes targeting Houthi leaders, their weapons and arsenals this spring, according to U.S. officials. For once period, starting in mid-March, the cost of the operation was estimated at $247 million, according to a U.S. official briefed on the matter but no authorized to speak publicly.

The real cost, the official said, is likely far higher. The military has lost several high tech aircraft, including seven MQ-9 Reaper drones and one Navy F-18 warplane, valued alone at nearly $70 million. That jet fell off the aircraft carrier USS Truman while it evaded a Houthi attack.

Civilian casualties

Houthi authorities say dozens of civilians have been killed since the Trump administration launched the operation. An April 28 strike that hit a detention center housing African migrants killed at least 68 people, according to Houthi media reports.

Another 74 died in strikes on a fuel terminal last month in the deadliest attack since the U.S. bombing campaign began, according to the health ministry. Hundreds have been injured, they say.

Aid groups have raised alarm about the high civilian death toll, while the Trump administration scrapped policies to reduce civilian harm.

“U.S. airstrikes are appearing to kill and injure civilians in Yemen at an alarming rate over the past month under a Trump administration that has loosened policy constraints on the use of force and is seeking to marginalize Pentagon offices charged with mitigating civilian harm,” Niku Jafarnia, a Yemen researcher at Human Rights Watch, said in a statement.