The White House announced that it will provide Ukraine with $335 million more in "security assistance" after a meeting on March 31 between U.S. Vice President Joe Biden and Ukrainian President Petro Poroshenko.
The aid is badly needed as Ukraine has faced an acute economic crisis since Russia annexed Crimea in 2014 and fomented a separatist revolt in Ukraine's east.
While Washington supports Ukraine's pro-Western government, it has been concerned about corruption in Kyiv. Those concerns were addressed in part earlier this week when Ukraine's parliament sacked the country's chief prosecutor, who allegedly was stalling high-profile corruption investigations.
The White House said Biden told Poroshenko that more aid will come if he keeps up efforts to install a new reform-minded government.
An attempt earlier this week to form a new governing coalition failed after one faction raised demands that would have rolled back some reforms sought by the West.
"The vice president welcomed the efforts...to form a stable, reform-oriented government, and stressed that this step, as well as the enactment of needed reforms, are critical to unlocking international economic assistance, including the third $1 billion U.S. loan guarantee," the White House said.