Middle East crisis live updates: Houthis say U.S., U.K. will pay a 'heavy price' after Yemen strikes

This is CNBC's live blog tracking developments in the Middle East and the Red Sea crisis. See below for the latest updates.

A Houthi official pledged retaliation after the U.S. and U.K. launched strikes against the group's targets in Yemen, in response to a wave of maritime attacks that have destabilized traffic in key trade routes in the Red Sea.

"America and Britain will undoubtedly have to prepare to pay a heavy price and bear all the dire consequences of this blatant aggression," Houthi senior official Hussein al-Ezzi said in a Google-translated update on the X social media platform.

Other Houthi officials have slammed the attack as unjustified and "barbaric," threatening more targeting of Israeli ships or of vessels heading to the occupied Palestinian territories.

U.S. President Joe Biden announced the strikes late on Thursday, in an escalation of tensions that have been brewing in the Middle East since the Hamas terror attacks against Israel of Oct. 7 and the Israeli Defense Forces' ensuing campaign in the Gaza Strip.

The Houthis, who share Iranian backing with Hamas, have claimed solidarity with the Palestinian people, conducting multiple strikes against ships they deem linked to Israel and pushing several shippers to reconsider routes through the Red Sea. The offensives culminated in the largest fusillade of Houthi drone and missile fire against shipping earlier this week — and in a U.S.-U.K.-led response overnight.

"Today, at my direction, U.S. military forces — together with the United Kingdom and with support from Australia, Bahrain, Canada, and the Netherlands — successfully conducted strikes against a number of targets in Yemen used by Houthi rebels to endanger freedom of navigation in one of the world's