The aid package underscores "our unwavering commitment to (Ukraine) as they continue to battle back against Russian aggression," National Security Council spokesman John Kirby told journalists.

US Secretary of State Antony Blinken said the aid would be drawn from American stockpiles and "includes air defense interceptors, munitions for rocket systems and artillery, multi-mission radars, and anti-tank weapons."

The equipment "will help Ukraine protect its troops, its people and its cities from Russian attacks and reinforce its capabilities across the front lines," he said in a statement.

The United States has been a key military backer of Ukraine, committing more than $55 billion in weapons, ammunition and other security aid since Russia launched its full-scale invasion in February 2022.

The latest aid announcement comes as Kyiv's troops press an attack into Russia's western Kursk region -- a surprise offensive that appears to be the most significant attack on Russian soil since Moscow launched the invasion of its neighbor.

Kirby said that the United States is "in touch with our Ukrainian counterparts, and we are working to gain a better understanding of what they're doing, what their goals are, what their strategy is."