The latest shipment, including defensive equipment and munitions, is part of $200 million in security assistance to Ukraine from the United States.
The United States has stepped up deliveries of weapons to Ukraine with a new batch arriving in Kiev after Secretary of State Antony Blinken confirmed another $200 million in aid to Ukraine.
At a ceremony for the latest shipment on Tuesday, US Charge d'Affaires in Ukraine Kristina Kvien said the aid will support "Ukraine's sovereign right to self-defence."
However, "our preference is diplomacy," said Kvien amid escalating tensions with Russia.
Ukrainian Deputy Defense Minister Rostislav Zemlinsky thanked the US for the aid that supports Kiev's struggle "to restore sovereignty and independence."
The US moves are being done in tandem with actions by other NATO member governments to bolster a defensive presence in Eastern Europe.
Denmark, for example, is sending a frigate and F-16 warplanes to Lithuania; Spain is sending four fighter jets to Bulgaria and three ships to the Black Sea to join NATO naval forces, and France stands ready to send troops to Romania.
'No intention' to send US troops
US President Joe Biden has "no intention" to send American troops to Ukraine, the White House said on Tuesday.
"There is no intention or interest or desire by the president to send troops to Ukraine," White House Spokesperson Jen Psaki told reporters.
The comments come after the Pentagon announced roughly 8,500 Americans troops have been put on heightened alert in the US in case they are needed to deploy to Europe as part of NATO's Response Force.
Unveiling ways that Western allies intend to inflict "massive consequences" on Russia's economy in the event of an invasion, a senior US official also warned Moscow against using energy exports as a weapon.
"We are prepared to implement sanctions with massive consequences" that go far beyond previous measures implemented in 2014 after Russia invaded Ukraine's Crimea region, the official told reporters, speaking on condition of anonymity.
British Prime Minister Boris Johnson echoed the threat, saying sanctions would be "heavier than anything we've ever done before."