The United States will conduct more strikes against Iran's proxy militias after three countries were targeted in two days as the US vows to crack down on Iranian attacks on US facilities in the region.

“It began with strikes on Friday night but that is not the end of it," White House National Security Adviser Jake Sullivan told NBC News on Sunday following over 85 attacks on Iraq and Syria Friday night. "We intend to take additional strikes and additional action to continue to send a clear message that the United States will respond when our forces are attacked, or people are killed,” he added.

On Saturday night, in a joint operation with Britain, the United States initiated dozens of strikes against Iran's Yemeni proxy, the Houthis, which is currently blockading the Red Sea in a bid to force Israel into a ceasefire amidst the war in Gaza against the Iran-backed Hamas militia, sparked by Hamas's invasion of Israel on October 7. Around 1,200 mostly civilians were murdered and at least 250 more taken hostage.

As a result of the US support for Israel's right to defend itself, Iran's proxies have waged at least 160 attacks on US facilities across the Middle East since October 7.

The barrage of airstrikes were launched in response to an assault on a base in Jordan last Sunday which resulted in the deaths of three American troops and injuries to approximately 40 others.

“We do believe that the strikes had good effect and degrading capability to these militant groups that attacked us,” he said. “And we do believe that as we continue, we will be able to continue to send a strong message about the United States [and its] firm resolve to respond when our forces are attacked.”

The US military (CENTCOM) reported on Friday that in the initial round of strikes in Iraq and Syria against Iran's Islamic Revolutionary Guards Corps (IRGC) Quds Force and associated militia groups, more than 85 targets were hit.

Speaking separately to Fox News Sunday, White House national security spokesman John Kirby also dubbed Friday night's strikes the "first round" of action.