Mourners leave flowers in Kiev's Independence Square on Monday in honor of antigovernment protesters killed in clashes with state riot police over the past week. Agence France-Presse/Getty Images
BRUSSELS—Europe and the U.S. grappled with how to pull together billions of dollars in financing for Ukraine to fend off its economic collapse in the aftermath of weeks of political crisis and violent street protests.
Amid Ukraine's increasingly dire financial situation, European Union negotiators are facing a thicket of rules governing how the 28-nation bloc can lend money to prop up its neighbors. The EU and the U.S. want the International Monetary Fund involved to force long-delayed reforms from Kiev in exchange for cash. But IMF programs can take weeks to negotiate, while Ukraine may not have that long.
"We have to help them soon—this month, next month," said Elmar Brok, chairman of the European Parliament's foreign-affairs committee, who was in Kiev meeting with Ukrainian officials. "Hopefully everyone is flexible to do that."
The U.S., the U.K. and some other European officials said the IMF is best placed to provide aid to Ukraine. U.S. Treasury Secretary Jacob Lewbacked IMF aid for Ukraine, after speaking by phone with IMF chief Christine Lagarde and Arseniy Yatsenyuk, one of the opposition leaders and a former foreign minister, a U.S. Treasury official said.
"Such support could be provided quickly once requested by the new government," U.K. Foreign Secretary William Hague said.
Ukraine's acting finance minister said on Monday that the government would seek a loan from the U.S. and Poland within one to two weeks. By the end of 2015, Ukraine hopes to raise some $35 billion from the IMF and Europe to revamp the economy and repay its foreign debt. But to get that aid, a yet-to-be-formed government would have to carry out unpopular measures that had been shot down by former President Viktor Yanukovych before his removal from power and other Ukrainian authorities.

Public Funerals in Kiev

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A man placed a candle at a memorial for the people killed in clashes at Independence Square in Kiev, Ukraine, Monday. Associated Press
Those measures include allowing the currency to devalue, slashing the budget deficit, and cutting huge government subsidies that keep energy prices contained.
Standard & Poor's Ratings Services estimates that the government, the central bank and state-owned gas company Naftogaz must spend $13 billion to service foreign-currency debt this year.
Europe and the U.S. face the risk Russia could make matters far worse by raising the price it charges Ukraine for natural gas. Such a move would siphon more precious hard currency reserves out of the country.
Ukraine's acting government declared ousted President Viktor Yanukovych a fugitive and said it was opening a criminal case into the "mass murder" of civilians stemming from violent clashes in the capital last week that left dozens dead. Photo: Getty.
"It might well be that a lot of the burden could fall on us," a euro-zone finance official said.
Ukraine's foreign-currency reserves have been falling steadily in recent months, to $17.8 billion at the start of February from $20 billion at the beginning of this year. That was before the Ukrainian crisis turned deadly, as government security forces killed scores of protesters camped out in Kiev's Maidan square.
Catherine Ashton, the EU's foreign-affairs chief, was in Kiev on Monday to discuss possible political and economic assistance. Top finance-ministry officials from the 28 EU nations are scheduled to meet in Brussels on Thursday, where the situation in Ukraine will likely be discussed, officials said.