The U.S. will send $400 million in new military aid to Ukraine, including precision-guided rockets.

The United States will rush more precision-guided rockets and additional ammunition to Ukraine to help resupply what officials have described as Kyiv’s dangerously low artillery stockpile.

The additional medium-range rockets — known as GMLRS and pronounced “Gimmlers” — are for the truck-mounted multiple-rocket launchers known as HIMARS that the United States already provided and which have, over the past year, proved crucial in bolstering Ukraine’s momentum in the war.

The rockets are part of what U.S. officials described as an estimated $400 million package set to be announced on Friday as President Biden hosts a short visit by Chancellor Olaf Scholz of Germany, bringing the total value of American military aid to Ukraine to more than $32 billion since February 2022.

The package expected to be unveiled on Friday also includes more ammunition for the 109 Bradley Fighting Vehicles that the United States pledged to Ukraine in January and began arriving in Ukraine last month, along with howitzer rounds, demolition munitions for obstacle clearance, spare parts and field equipment.

NATO leaders have long warned of a looming artillery shortage for Ukraine as its troops burn through thousands of shells each day in trying to push back Russian forces. That has been particularly clear in the monthslong battle for the city of Bakhmut in eastern Ukraine, where Ukrainian troops are fighting to avoid encirclement by Russian forces.

It was not clear if the new tranche of American ammunition would arrive in time to defend Bakhmut, if that is where commanders decide it should be sent.

But the satellite-guided rockets add significant firepower to the HIMARS launchers that were key to helping Ukraine reclaim territory in a rapid counteroffensive against Russian forces in the northeastern Kharkiv region last summer.

Gen. Mark Milley, the chairman of the Joint Chiefs of Staff, said Thursday that the Biden administration would try to give Ukraine as much aid as it could in the coming months.

He said that in addition to providing missiles, tanks, ammunition and fighting vehicles, the Biden administration is intent on boosting Ukraine’s air defenses, a task which Pentagon war planners deem critical. Western officials have warned that Moscow could quickly gain a stronger hand if Ukraine runs out of the Stinger missiles and other air-defense weapons that it has successfully used over the past year to keep Russian war planes at bay.

“This is a war of aggression by Russia against Ukraine,” General Milley said to reporters traveling with him on a visit to U.S.-hosted exercises for Ukrainian military officers in Wiesbaden, Germany. “What we’re doing is helping Ukraine defend itself.”

Already, the United States has sent thousands of GMLR missiles and 38 HIMARS launchers. Germany and Britain also have sent similar systems.

The Bradley vehicles were part of a wave of tanks and other combat vehicles that more than a dozen nations committed in January to send to Ukraine ahead of a renewed Russian offensive in eastern Ukraine.