The United States has signed a $US1 billion ($A1.07 billion) loan guarantee for Ukraine in support of its economic recovery after weeks of upheaval and the loss of Crimea to Russia.
It comes as pro-Russian insurgents gain ground in eastern Ukraine, occupying a police station and an administrative building, their latest seizures in a campaign threatening to break up the ex-Soviet state.
"The Ukrainian people have demonstrated tremendous courage as they have charted an independent course for their country and demanded a government that truly reflects the will of the people," US Treasury Secretary Jacob Lew said on Monday in a statement.
"The United States has been at the forefront of building international support for Ukraine, and holding Russia accountable for its violation of Ukrainian sovereignty and destabilizing action."
Lew signed the agreement with Ukrainian Finance Minister Oleksandr Shlapak at the Treasury's Washington headquarters following talks.
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The deal is "a sign of unconditional support from the US for the aspirations of the Ukraine people to freedom, democracy and European values," Shlapak said at the signing ceremony.
The US loan guarantee, available immediately, will reinforce the Ukrainian government's efforts to provide critical services as it implements reforms, while protecting the most vulnerable households from the impact of the necessary economic adjustment, Lew said.
The US Treasury chief praised the work of Shlapak and his team in setting up a comprehensive economic reform program together with the International Monetary Fund.
The IMF is discussing financial assistance of $US14-$18 billion for Ukraine, part of a $US27 billion rescue being mounted by the World Bank and Western powers.
