The visit comes a day after Zelenskyy greeted troops in Bakhmut, a front-line city that Moscow's forces have struggled to seize despite months of intense battles, while Russian President Vladimir Putin offered a rare admission of his army's difficulties.
The Russian leader’s pre-Christmas trip to neighboring Belarus only added to mounting speculation.
Zelenskyy will now meet with President Joe Biden and address Congress as his country hopes to not just shore up but secure greater support from its Western allies.
"Ukraine is very keen to step up and intensify the military support from the U.S.," Frank Ledwidge, a senior lecturer of law and strategy at University of Portsmouth, told NBC News.
On Monday, Putin and his most senior advisers traveled to the Belarusian capital, Minsk, to meet authoritarian ally President Alexander Lukashenko, amplifying long-held fears that his forces could join a new offensive.