It comes as an aid bill in Congress stalls and as Ukrainian troops run out of battlefield supplies.
The US will send $300m (£234m) in military weapons to Ukraine, including ammunition, rockets and anti-aircraft missiles, the White House has said.
The surprise announcement comes as a bill in Congress to send further aid to Ukraine stalls amid partisan debate.
The US shipment, the first in nearly three months, is intended to prevent Ukraine from losing ground to Russia.
National Security Adviser Jake Sullivan said this aid "is nowhere near enough to meet Ukraine's battlefield needs".
"This ammunition will keep Ukraine's guns firing for a period, but only a short period," Mr Sullivan told reporters on Tuesday, adding that "it will not prevent Ukraine from running out of ammunition."
Yep remember all that showmanship about how the Republicans in Congress are evil and preventing aid. Well, then white house just decided to send it anyway, as if that wasn't always an option...
You guys are trying so hard to make Biden look bad at the benefit of making Trump look good and it doesn't even compare. Trump is a piece of shit and anyone who supports him needs to realize they are being conned. He is a con artist first. You are a rube. Gullible. Foolish. If you believe he is telling you the truth then you have been tricked. Trump wants to dismantle all aid to any country threatened by Russia, Iran, North Korea and anyone else that might have actually donated some significant amount of "Foreign Aid" to his campaign funds and legal funds. The man is nearly half a billion in the hole because of the recent court cases against him. You really expect him to not take money from literally anyone at this point to pay those legal fees? Seriously? The man is a walking security risk with such a large fine on his hands. He is too hot to elect. He is one step short of being a fucking felon and you want to conflate him as being somehow better than Biden? Fuck all the way off dude.
I'm always impressed at how technology has evolved enough to allow people as retarded as you to manage navigating the internet to type braindead shit like this
As a developer from Budapest, why do you give a fuck about US politics? I don't have any opinions on the politics of Budapest because I don't give a fuck. I don't live there. It's not my problem.
The way they operated until now is they donated an expiring munition to Ukraine, and then used the money Congress gave to replenish their own such with brand new ones.
Now the ammunition they are donating, they can't replenish thanks to Republicans.