President Joe Biden has told his Ukrainian counterpart, Volodymyr Zelenskyy, that the United States will provide a small number of long-range missiles to aid the war with Russia, three U.S. officials and a congressional official familiar with the discussions told NBC News on Friday.

The officials, who were not authorized to speak publicly, did not say when the missiles would be delivered or when a public announcement would be made.

For months, Ukraine has asked for the Army Tactical Missile System, known as ATACMS, which would give Kyiv the ability to strike targets from as far away as about 180 miles, hitting supply lines, railways, and command and control locations behind the Russian front lines.

Defense officials have said the U.S. does not have a large stockpile of excess ATACMS, which have a bigger payload than traditional artillery, to provide to Ukraine. Also, some in Washington have resisted supplying the weapon, known colloquially as “attack-ems,” out of fear that it would widen the war with Russia.

The congressional official said there was still a debate about the type of missile that would be sent and how many would be delivered to Ukraine. They added that countries in Eastern Europe had already given Ukraine large portions of their weapons stockpiles.

This is a breaking news story. Please check back for updates.