Harris made the announcement at the Ukraine peace summit in Lucerne, Switzerland, where she met with Ukraine President Volodymyr Zelenskiy.
Group of Seven leaders have agreed to provide Ukraine with $50 billion via the use of frozen Russian assets by the end of the year, the French presidency said on Wednesday.
As President Biden's administration faces mounting scrutiny, dissent within the State Department highlights concerns over America's stance on international conflicts.
NATO chief Jens Stoltenberg and Hungarian Prime Minister Viktor Orban agreed on Wednesday that Budapest would "not block" the defense alliance from contributing more to Ukraine's fight against Russia's invasion.
The expanded measures, which are likely to be announced Wednesday, are part of the Biden administration's efforts to stop Russia's attempts to bypass Western sanctions and diminish its war capabilities against Ukraine.
Ukraine on Thursday ordered the evacuation of children and their guardians from several towns and villages in the eastern Donetsk region, where fighting with Russia is intensifying.
Zelenskyy will deliver an in-person speech at the Shangri-La Dialogue, considered Asia's premier defense summit.
The visit from Baerbock, who urged the West to supply Ukraine with more air defenses, came after more than two dozen Russian drones targeted Ukraine overnight, in an attack that left several wounded in the eastern Kharkiv region.
It is "vital and urgent" for the United States and allies to find a way to tap immobilized Russian assets in helping Ukraine, US Treasury Secretary Janet Yellen said in prepared remarks released Monday.
US Secretary of State Antony Blinken was trying to send a message of defiance and hope when he took to the stage of a Kyiv bar on Tuesday night for a guitar performance of "Rockin' in the Free World".
The military gave details of the pull back as US Secretary of State Antony Blinken was on an unannounced visit to Kyiv where President Volodymyr Zelensky urged him to speed up US supplies of weapons.
Ukraine on Wednesday warned of possible power shutdowns across the country after a "massive" wave of Russian missiles and drones targeted the battered Ukrainian energy system.
Russia has added Ukrainian President Volodymyr Zelensky to its list of wanted criminals, a move Kyiv dismissed as a sign of Moscow's "desperation".
Russia's wanted list also encompasses numerous officials and lawmakers from Ukraine and NATO countries.
A Ukrainian man was sentenced to more than 13 years in prison in Texas on Wednesday for his role in ransomware attacks by the notorious Russia-based REvil hacking group, the US Justice Department said.
Five people were killed Wednesday as Russia struck Ukraine's eastern Kharkiv and Donetsk regions, local officials said.
The Gaza Strip is filled with more war debris and rubble than Ukraine, the head of UN demining operations for the narrow Palestinian territory said Wednesday.
Kyiv authorities on Tuesday began taking down a Soviet-era monument celebrating friendship with Russia -- more than two years into an invasion by Moscow which has cost tens of thousands of lives.
Hunter Biden has threatened legal action against Fox News, accusing the network of defamation and exploitation of his image.
Russia has stepped up devastating bombardments on Ukrainian power plants in recent weeks, at a perilous moment for Kyiv as it struggles with manpower and ammunition shortages and loses ground on the front.
The newly approved aid, totaling billions of dollars, marks a significant gesture of support from the United States to bolster the security and stability of both nations.
The vote, which commenced ahead of schedule, saw 210 Democrats and 101 Republicans supporting the measure, while 112 Republicans dissented.