Ukraine eagers to amend the present agreement under which its transits Russian oil shipments to the EU, a spokesman for Ukraine's state oil pipeline operator Ukrtransnafta told reporters Monday.
"The current contract was signed in 2004," Ukrtransnafta spokesman Sergei Zinkevich said. "Ukraine wants to amend it."
Zinkevich indicated that the dispute centred on volumes of oil Russia would guarantee to pump through Ukraine to clients downstream in the European Union and said negotiations were continuing on this matter.
Zinkevich's confirmation of a problem came shortly after Slovakia announced that Russia had warned it could suspend oil supplies shipped through Ukraine to three European Union countries.
He confirmed that Ukraine asked Russia to pay Kiev higher transit tariffs on the oil it ships to Europe and said the two sides had reached a "satisfactory compromise" on the fees.
However, "negotiations are still under way" between Russia and Ukraine on a "guarantee" of the volume of oil -- subject to the transit fees for Kiev -- that Russia would pump through the pipeline network in Ukraine, he said.
"The amount of oil that Russia currently ships via Ukraine at present leaves something to be desired," Zinkevich said.
He said Russia wanted to portray Ukraine as the guilty party in the current dispute, but added: "I do not see Ukraine's guilt."
Zinkevich predicted that the latest energy dispute between the two ex-Soviet giants would be quickly resolved, but said an interruption to Russian oil supplies transiting Ukraine could not be ruled out.
"It is not Ukraine that delivers the oil but Russia," he said. "We are ready to pump it" as long as it keeps coming.
AFP has contributed to the report.