Pentagon says 'over 20 nations' have joined Operation Prosperity Guardian

Pentagon Press Secretary Maj. Gen. Pat Ryder speaks during a briefing at the Pentagon in Washington, on Tuesday, Dec. 12. (AP/Susan Walsh)

Pentagon Press Secretary Maj. Gen. Pat Ryder said Thursday that "we've had over 20 nations now sign on to participate" in Operation Prosperity Guardian, the U.S.-led effort to protect ships from attacks by Yemen's Iran-backed Houthi rebels in the Red Sea.

"The forces assigned to Operation Prosperity Guardian will serve as a highway patrol of sorts, patrolling the Red Sea and the Gulf of Aden to respond to and assist as necessary commercial vessels that are transiting this vital international waterway," Ryder said during a press briefing. "It's a defensive coalition meant to reassure global shipping and mariners that the international community is there to help with safe passage. 

Ryder also said "In the days ahead, the United States will continue to consult closely with our allies and partners who share the fundamental principle of freedom of navigation" and "we expect to see the coalition continue to grow."

"The Houthis need to stop these attacks. They need to stop them now," Ryder warned. "You know, that's clear and simple. And they really need to ask themselves if they've bitten off more than they can chew when it comes to taking on the entire international community and negatively impacting billions of dollars in global trade, economic prosperity and international law.