Ukraine's first lady, Olena Zelenska, is in the US for a series of high-level meetings and an address to Congress.
Her visit comes four months after her husband, President Volodymyr Zelensky, made a virtual speech to Congress, pressing for more military equipment.
Ms Zelenska met Secretary of State Antony Blinken on Monday and is due to hold talks with her counterpart Jill Biden on Tuesday, the White House said.
She is due to deliver remarks to lawmakers on Capitol Hill on Wednesday.
Tuesday's encounter will be the second time the two first ladies have met, after Dr Biden made an unannounced visit to Ukraine in May.
Ms Zelenska has no official portfolio in the Ukrainian government. But after nearly five months of Russia's war in Ukraine, Kyiv is keen to seek more military aid and political backing from the US.
Congress has already approved nearly $40bn (£33bn) in aid to Ukraine that is due to be fully delivered by the end of September.
On Monday, Ms Zelenska also met Samantha Power, head of the US Agency for International Development.
The agency has given billions of dollars to support Ukraine's government and for humanitarian needs, as well as working to tackle a global food shortage aggravated by Russia's war.
