7.62 caliber ammunition production at Lake City Army Ammunition Plant in Missouri. (Dori Whipple/Lake City Army Ammunition Plant)

WASHINGTON — A shipment of ammunition being transported from Iran to rebels in Yemen was intercepted by a U.S. Navy ship and redirected to Ukrainian troops fighting off Russian invaders, U.S. defense officials said Wednesday.

U.S. Central Command said the shipment included 1.1 million rounds of 7.62 mm ammunition that can be fired by multiple Soviet-era assault rifles used by Ukraine, a former Soviet republic.

The bullets were being transported by Iran’s Islamic Revolutionary Guard Corps to Houthi fighters in Yemen aboard an unflagged traditional wooden sailing ship, officials said. The IRGC is a component of the Iranian military.

U.S. naval forces seized the bullets in December and turned them over to the Ukrainian military Monday, CENTCOM said.

“The U.S. is committed to working with our allies and partners to counter the flow of Iranian lethal aid in the region by all lawful means,” according to CENTCOM, which oversees operations in the Middle East. “Iran’s support for armed groups threatens international and regional security, our forces, diplomatic personnel and citizens in the region.”

The U.S. Navy’s Mideast-based 5th Fleet and its allies have intercepted numerous ships believed to be transporting weapons and ammunition from Iran to Yemen in support of the Iranian-backed Houthis. This is the first time that the seized weaponry has been handed over to Ukraine, Capt. Abigail Hammock, a CENTCOM spokeswoman, told The Associated Press.

The Navy intercepted more than 2,100 AK-47s that were being shipped in the same fashion — by an unflagged fishing boat — from Iran to Yemen in early January, but military officials have not yet said whether some of those weapons also might be sent to Ukraine.

Thousands of AK-47 assault rifles sit on the flight deck of guided-missile destroyer USS The Sullivans during an inventory process on Jan. 7, 2023. U.S. naval forces seized 2,116 AK-47 assault rifles from a fishing vessel transiting along a maritime route from Iran to Yemen. (U.S. Navy)

Iran has not been directly involved in the Yemen civil war, which has been going since 2014. However, U.S. officials have said the IRGC and proxy networks have been active in shipping arms to Houthi rebels to fight against the Yemeni government, which is supported by the United States, France and Britain.

The shipment of Iranian ammunition to Ukraine comes as the Pentagon is urging Congress to authorize more military aid to help Ukrainian forces beat back a Russian invasion. U.S. defense officials said last week that they are running low on money to replace weapons sent from U.S. stockpiles to Ukraine and to ship more arms to the country, which has been defending against Russian forces since February 2022.

“We have already been forced to slow down the replenishment of our own forces to hedge against an uncertain funding future,” Pentagon Comptroller Michael McCord wrote in a letter to House and Senate lawmakers. “Failure to replenish our military services on a timely basis could harm our military’s readiness.”

The White House asked Congress in August to approve $24 billion in aid to Ukraine, including $13 billion in military assistance. The money was expected to be included in the short-term spending agreement approved last week to keep the government open but was stripped away as Republicans in the House rebelled against continued funds for the Eastern European country.

President Joe Biden said Wednesday that he’s concerned about the impact the GOP-led disruption in Congress could have on further Ukrainian aid.

“It does worry me, but I know there are a majority of members of the House and Senate in both parties who have said that they support funding Ukraine,” he said. “I’m going to make the argument that it’s overwhelmingly in the interest of the United States of America that Ukraine succeed.”