The U.S. on Friday accused Iran of close involvement in attacks on commercial ships by Yemen's Houthi rebels, stepping up the tone as Washington considers tougher measures including possible force.

The White House publicly released U.S. intelligence as the Iranian-linked Yemeni insurgents persist with ship strikes they say are in solidarity with Palestinians in the Gaza Strip, where Israel is battling Hamas militants.

The White House said that Tehran's clerical state has provided drones and missiles to the Houthis as well as tactical intelligence.

"We know that Iran was deeply involved in planning the operations against commercial vessels in the Red Sea," National Security Council spokeswoman Adrienne Watson said.

"We have no reason to believe that Iran is trying to dissuade the Houthis from this reckless behavior," she said.

The Houthis, who control vast parts of the Arabian Peninsula's poorest country, including the capital Sanaa, have launched more than 100 drone and missile attacks, targeting 10 merchant vessels, according to the Pentagon.

On Tuesday, Defense Secretary Lloyd Austin held an emergency meeting with defense officials from dozens of countries, along with the European Union and NATO, to address what he called "reckless, dangerous" attacks which "violate international law."

Last week, U.S. Central Command reported that the USS Carney, a guided missile destroyer, shot down 14 attack drones suspected to have been fired from Houthi-controlled regions of Yemen.

In a Nov. 15 interview with CBS News, Iranian Foreign Minister Hossein Amir-Abdollahian denied that Iran was responsible for a drone fired from Yemen that was shot down by the guided-missile destroyer USS Thomas Hudner. The drone appeared to be targeting the Hudner, U.S. officials said at the time.

"We really didn't want this crisis to expand," Amir-Abdollahian told CBS News, referencing the Israel-Hamas war. "But the U.S. has been intensifying the war in Gaza by throwing its support behind Israel. Yemen makes its own decisions and acts independently." 

Earlier this week, energy giant BP announced it was temporarily suspending all gas and oil shipments in the Red Sea because of the attacks.  

And with commercial traffic disrupted, the U.S. recently announced a multinational naval task force of more than 20 countries to protect vessels transiting the Red Sea.

In a show of force, the aircraft carrier USS Dwight D. Eisenhower has entered the Gulf of Aden.

Rebel leader Abdel-Malek al-Houthi warned Wednesday that if they were attacked, the rebels would strike back against "American battleships, American interests and American navigation."

The White House said that U.S. visual analysis found nearly identical features between Iran's KAS-04 drones and the unmanned vehicles fired by the Houthis, as well as consistent features between Iranian and Houthi missiles.

The Houthis are also reliant on Iranian-provided monitoring systems at sea, the White House said.

"Moreover, Iranian-provided tactical intelligence has been critical in enabling Houthi targeting of maritime vessels since the group commenced attacks in November," Watson said.

The Biden administration had initially kept a low-key tone on the Houthi attacks, in part out of an interest in preserving a fragile peace in Yemen.

The Houthis and the Saudi-backed government have effectively maintained a United Nations-brokered truce since April 2022, halting a devastating war that triggered a humanitarian crisis in which most of the population relies on aid.

Iran's religious leadership openly supports Hamas, whose gunmen broke through Gaza's militarized border on Oct. 7 and killed more than 1,200 people in Israel, mostly civilians, and abducted several hundred more.

U.S. officials have said they have no evidence that Tehran had previous knowledge or directly planned the attack.

Israel has vowed to destroy Hamas. Its relentless bombardment and ground invasion of Gaza has killed more than 20,000 people, most of them women and children, according to Hamas authorities.

In:
• Iran
• Red Sea
• Houthi Movement
• Yemen