WASHINGTON (AP) — The U.S. announced a new $400 million package of military aid for Ukraine on Friday, as Kyiv struggles to hold off advances by Russian troops in the northeast Kharkiv region.

This is the third tranche of aid for Ukraine since Congress passed supplemental funding in late April after months of gridlock. Ukrainian President Volodymyr Zelenskyy had warned Thursday that his country was facing “a really difficult situation” in the east, but said a new supply of U.S. weapons was coming and “we will be able to stop them.”

The package includes High Mobility Artillery Rocket Systems (HIMARS) and rockets for them, as well as munitions for Patriot and National Advanced Surface-to-Air Missile Systems, artillery, anti-aircraft and anti-tank munitions, and an array of armored vehicles, such as Bradley and Mine Resistant Ambush Protected vehicles.