The package nearly halves the available US$2.21 billion remaining in Ukraine Security Assistance Initiative as the Biden administration works to commit to buying weapons from industry, rather than pulling from US weapons stocks.

The USAI funds will be put toward buying ammunition for High Mobility Artillery Rocket Systems (HIMARS) made by Lockheed Martin as well as drones and spare parts to maintain artillery equipment, according to the Pentagon.

Announcement of the package came on Saturday as the defense industry and policy makers meet at the annual Reagan National Defense Forum in California.

The Biden administration has often used Presidential Drawdown Authority, which authorises president Joe Biden to transfer excess articles and services from US stocks without congressional approval during an emergency.

The USAI funds are separate and will go to purchase new weapons from industry.

The Biden administration still has about US$6 billion of congressionally granted presidential drawdown authority, including funds authorised in 2024 and funds discovered by the Pentagon after overestimating the value of arms shipped to Ukraine.

Since the Russian invasion in February 2022, the US has committed more than $62 billion worth of security assistance to Ukraine.