Lagarde's intervention came as an International Monetary Fund mission arrived in Kyiv to assess Ukraine's committment to economic restructuring and belt-tightening measures that would unlock money that could help the cash-starved government stay float, Censor.NET reports citing YahooNEWS.
That money is vital to help keep Ukraine on its path toward Europe and cushion the blow of the 17-month pro-Russian separatist war.
But not everything is going according to Kyiv and the Fund's plan.
A group of smaller private lenders have reportedly refused to join a debt write-down agreement that Ukraine had struck with its four largest commercial bondholders last month.
Moscow is also demanding the December repayment of a $3.0 billion bond it had issued to Russian-backed president Viktor Yanukovych in the months preceeding his February 2014 ouster by waves of pro-European protests.
"High participation by all concerned Eurobond holders in the upcoming debt exchange is paramount, since Ukraine lacks the resources under the programme to service its debts on the original terms. Together with the authorities and the Ad-Hoc Creditor Committee, I call on all creditors to support this offer," Lagarde said in a statement.
The IMF hopes that Western assistance will not only help Ukraine reverse its three-year recession and adopt global production standards but also halt its diplomatically-costly reliance on Moscow's financial help.
The separatist war that Russia denies fomenting in Ukraine's vital industrial heartland will likely see the economy shrink by as much as 10 percent this year.
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