Updated July 6, 2023 at 2:42 PM ET

U.S. officials tell NPR that the Biden administration plans to send cluster bombs, or munitions, to Ukraine to target dug-in Russian forces. An announcement is expected tomorrow.

The controversial weapons drop dozens of bomblets that human rights groups say endanger civilians.

Ukraine and Russia are already using cluster munitions on the battlefield, but Ukraine is running low on ammunition and has pressed the U.S. to send such weapons.

Officials say the cluster bombs will be effective against Russian forces in strong defensive positions as well as command and control headquarters.

More than 100 countries ban such weapons because unexploded bomblets can be picked up by civilians, causing injury or death. Cluster bombs release a larger number of bomblets over a wide area, and they can continue to pose a deadly risk even long after the fighting has ceased.

The U.S. has a large stockpile of cluster munitions and used them in both the Afghan and Iraq wars.

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