US President Joe Biden on Thursday announced nearly $8 billion in military aid to Ukraine, with the package coming at a critical moment in the war against Russia.
“We have to strengthen Ukraine's defences,” Mr Biden told reporters before a meeting with Ukrainian President Volodymyr Zelenskyy, adding he had directed the Pentagon to allocate to Kyiv all remaining security system funding for Ukraine.
“This will strengthen Ukraine's position in future negotiations … We look ahead to help Ukraine succeed in the long term.”
Mr Biden pledged to “provide Ukraine with the support it needs to win this war”.
The aid is part of a spending package approved in April after a drawn-out fight with Republicans in Congress. Mr Biden said all of the $60 billion approved for Ukraine would be disbursed before he leaves office in January.
The package includes $5.5 billion to be allocated before the end of the fiscal year and $2.4 billion under the Ukraine Security Assistance Initiative, which allows the US to buy weapons for Kyiv from private companies instead of withdrawing them from its own stockpile.
Ukraine will be receiving more air-defence systems, drone systems and air-to-ground munitions, as well as another Patriot air-defence battery. Mr Biden also directed the Pentagon to increase training for Ukrainian F-16 pilots.
“Let me be clear: Russia will not prevail in this war. Russia will not prevail. Ukraine will prevail, and we'll continue to stand by you every step of the way,” Mr Biden said.
Mr Zelenskyy thanked Mr Biden and the US for its “strong support”.
“We have a strong security agreement with United States and we are grateful for it, and we will fully implement it,” he said. “And it's very important that we share the same vision for Ukraine's security future in the EU and Nato, and Ukraine is doing an unprecedented number of reforms on this path.”
Mr Zelenskyy said he had raised his “plan of victory” with Mr Biden and that they would be discussing the details in their meeting to “strengthen the plan; co-ordinate our positions, use and approaches”.
He is pushing the US and other western allies to allow his troops to use long-range missiles to strike deeper into Russia, which Mr Biden has repeatedly refused to approve.
"History has shown us, if we allow aggressors like [Russian President Vladimir] Putin to take land with impunity, they keep going, and Putin could set his sights on Poland, the Baltic states and other Nato allies," Vice President Kamala Harris said later, speaking alongside Mr Zelenskyy.
"We also know that other would-be aggressors around the world are watching to see what happens in Ukraine ... As history is so clear in reminding us, the United States cannot and should not isolate ourselves from the rest of the world. Isolation is not insulation."
On Capitol Hill, Mr Zelenskyy's reception was somewhat awkward, indicating that consistent military support for Ukraine is far from certain.
He held a private meeting with bipartisan congressional leaders on Thursday morning, as tension over Ukraine festers between Republicans.
Republican Speaker of the House Mike Johnson, an ally of Kyiv-sceptical presidential candidate Donald Trump, refused to attend the meeting after demanding Mr Zelenskyy fire his US ambassador Oksana Markarova.
Ms Markarova visited a Pennsylvania weapons factory that included only Democrats, prompting Mr Johnson to accuse her of partisanship.
“Support for ending Russia’s war against Ukraine continues to be bipartisan, but our relationship is unnecessarily tested and needlessly tarnished when the candidates at the top of the Republican presidential ticket are targeted in the media by officials in your government,” Mr Johnson wrote in a letter to Mr Zelenskyy.
This is the latest row between Mr Zelenskyy and Republicans, in a struggle between the party's traditional anti-Russia hawks and some of Mr Trump's far-right allies, who appear to have sympathetic views towards Moscow.
Mr Zelenskyy told The New Yorker he believes Mr Trump's running mate, Senator JD Vance, is “too radical” and suggested he “read up” on the history of the Second World War.
Mr Vance has been a critic of funding for Ukraine and this month outlined his vision for ending the war, suggesting: “Russia gets the guarantee of neutrality from Ukraine – it doesn't join Nato.”
Mr Trump on Wednesday said Ukraine should have made concessions to Moscow before Russia's February 2022 attack, adding that even “the worst deal would’ve been better than what we have now”.
Mr Zelenskyy is expected to use his Washington visit to present a “victory plan”, which Ukrainian officials have said includes calls on western allies to put more political and economic pressure on Russia to reach a negotiated settlement to end the war.
Vice President Kamala Harris, the Democratic candidate, will meet Mr Zelenskyy later on Thursday. She has pledged to continue to support Ukraine should she win.
On Wednesday, on the margins of the UN General Assembly in New York, Mr Biden vowed to support Kyiv “now and in the future” as G7 leaders pledged to underwrite Ukraine's postwar recovery.
Mr Zelenskyy this week addressed the UN General Assembly and urged nations to seek “real, just peace”, instead of “a lull” in fighting.
He said there is no alternative to the “peace formula” first presented two years ago, which calls for the withdrawal of all Russian forces from Ukraine, the release of prisoners and accountability for war crimes.
