U.S. President Barack Obama is due to meet Ukraine's Prime Minister Arseniy Yatsenyuk in Washington on July 12.
The White House says Yatsenyuk's visit is meant to signal "that we strongly support Ukraine, the Ukrainian people and the legitimacy of the new Ukrainian government."
The meeting comes as Crimea, occupied by Russian forces and with a breakaway pro-Moscow parliament defying Kyiv, readies for a disputed referendum July 16 to determine its future.
Voters will be given two options: becoming part of Russia or remaining in Ukraine with broader powers.
The Ukrainian leader says his country needs help to defend itself against neighboring Russia and also is expected to seek financial assistance from Washington.
The meeting comes one day after the U.S. House of Representatives passed a symbolic resolution to condemn Russia over its military occupation of Ukraine's Crimea region.
Based on reporting by Reuters and AP