The administration of President Joe Biden is preparing approximately $800 million in additional military aid for Ukraine. According to three sources familiar with the situation, it could announce as early as Friday.

According to Reuters sources, Biden would authorize the help using his Presidential Drawdown Authority, which permits the president to transfer excess weaponry from U.S. stores.

The sources said anonymously that an announcement could be delayed until the following week. They cautioned that the value of the weapon bundles could vary before their information.

White House officials declined to respond.

Since February, when Russian troops invaded Ukraine in what Russian President Vladimir Putin labeled a "special military operation," the battle has become a war of attrition fought mainly in the east and south of Ukraine.

Washington has provided billions of dollars in security aid to the administration of Kyiv.