WASHINGTON, March 26 - Russia's $3 billion holding of Ukrainian debt should be classified as 'official' debt, an IMF spokesman said on Thursday, weighing in on what has become a contentious issue in Kiev's economic situation, Reuters reported.

Ukraine, which recently received a $17.5 billion bailout from the International Monetary Fund, must come up with at least $15.3 billion from sovereign debt restructuring under the conditions of the program.