The International Monetary Fund has agreed a $14bn to $18bn bailout for Ukraine, a deal that will unlock further credits to reach a total of $27bn over the next two years.
The agreement is intended to help Ukraine meet debt payments looming this year after months of anti-government protests that culminated in the overthrow of President Viktor Yanukovych and a standoff with Moscow in which Russia annexed the Crimea region.
"The mission has reached a staff-level agreement with the authorities of Ukraine on an economic reform programme that can be supported by a two-year standby arrangement with the IMF," the organisation said in a statement.
"The financial support from the broader international community that the programme will unlock amounts to $27bn over the next two years. Of this, assistance from the IMF will range between $14-18bn, with the precise amount to be determined once all bilateral and multilateral support is accounted for."
The agreement is subject to approval by the IMF's management and executive board, which will consider it in April.
"Following the intense economic and political turbulence of recent months, Ukraine has achieved some stability, but faces difficult challenges," the IMF statement said.
Announcing the agreement in Kiev, the IMF mission chief, Nikolay Gueorguiev, declined to say how big the initial tranche of aid would be.
Kiev has said it desperately needs cash to cover expenses and avert a possible debt default. The country's finance minister has predicted the economy will contract by 3% this year, weakened by years of mismanagement and political turmoil.
The bailout will help prop up Ukraine's economy and clear the way for several billion dollars in aid from the US, EU, Japan and other nations.
Ukraine's new leaders announced a radical 50% increase in the price of domestic gas on Wednesday with effect from 1 May, meeting an unpopular IMF condition that Yanukovych had refused.