Russia has long turned to Iranian-made drones to attack Ukraine. Now Ukrainian forces will be using bullets seized from Iran against Russia troops.

A U.S. Navy ship seized the 1.1 million rounds off of a vessel that was being used by Iran’s Islamic Revolutionary Guard Corps to arm Houthi rebels in Yemen’s civil war in violation of a U.N. Security Council resolution.

Those 7.62 mm rounds have now been transferred to Ukraine, U.S. Central Command said Wednesday. The much-needed ammunition has been sent at a time when continued U.S. financial support for Kyiv’s fight to defend itself remains in question.

The 7.62 mm ammunition is the standard round for Soviet-era Kalashnikov assault rifles and their many derivatives. Ukraine, as a former Soviet republic, still relies on the Kalashnikov for many of its units.

“With this weapons transfer, the Justice Department’s forfeiture actions against one authoritarian regime are now directly supporting the Ukrainian people’s fight against another authoritarian regime. We will continue to use every legal authority at our disposal to support Ukraine in their fight for freedom, democracy, and the rule of law,” Attorney General Merrick Garland said in a statement.

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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, Central Command spokeswoman Capt. Abigail Hammock said.

This shipment was seized by Central Command naval forces in December off of a vessel the command described as a “stateless dhow," a traditional wooden sailing ship, that was being used by the Islamic Revolutionary Guard Corps to arm the Houthis.

A fragile cease-fire is in place in Yemen after the almost decadelong war, but Iran has continued to supply the Houthis with lethal aid, Lt. Gen. Alexus G. Grynkewich, head of U.S. Air Forces Central, told reporters on Wednesday. He said this was a major threat to Yemen finding a durable peace.

U.S. Central Command said the U.S. “obtained ownership of these munitions on July 20, 2023, through the Department of Justice’s civil forfeiture claims against Iran’s Islamic Revolutionary Guard Corps.”

A United Nations arms embargo has prohibited weapons transfers to the Houthis since 2014. Iran insists it adheres to the ban, even as it has long been transferring rifles, rocket-propelled grenades, missiles and other weaponry to the Houthis via the sea.

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Independent experts, Western nations and U.N. experts have traced components seized aboard detained vessels back to Iran.

Iran's mission to the United Nations did not immediately respond to a request for comment on Wednesday.

Even though the shipment of more than 1 million rounds of small arms ammunition is substantial, it pales in comparison with the amount that the U.S. has already sent to Ukraine since Russia invaded in February 2022, much of which has already been used in the intense ground battle.

The U.S. has provided more than 300 million rounds of small arms ammunition and grenades as part of the almost $44 billion in military aid it has sent to help Ukraine.

Further U.S. funding for Ukraine's war was not included in a stopgap measure that prevented a government shutdown last weekend. With the ouster of Republican House Speaker Kevin McCarthy, it was unclear whether the future leader will be able to generate enough support from the party’s hard-liners, who have opposed sending more money to Ukraine.

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