The European Union says Russia has approved a plan that could result in a resumption of natural gas delivery to Europe, but Moscow has not confirmed the report.

Russian Prime Minister Vladimir Putin said Thursday Russia would resume gas shipments only if international observers can monitor the process to ensure Ukraine does not steal fuel, The Washington Post reported. Ukraine rejected the Russian proposal, and Russia rejected a European proposal, but EU officials released a statement late Thursday saying Moscow had approved a plan that "should lead" to a resumption of natural gas supplies to EU members, the Post said.

However, neither Russia nor Ukraine had confirmed the EU claim.

Russia's energy giant Gazprom claims Ukraine owes $614 million in late fees for gas deliveries and talks on Ukraine's 2009 contract have broken down. Russia says Ukraine siphoned gas intended for Europe.

Russia and Ukraine have blamed each other for the natural gas lockdown, which has left much of Europe cold, halting gas flow through the pipeline that delivers 80 percent of Russia's natural gas to Europe, The Times of London reported.

Several European countries have declared states of emergency as below zero temperatures gripped parts of the continent.

Bosnian Foreign Minister Sven Alkalay said "4 million of our citizens are in danger."

Austria, Bulgaria, Slovakia, the Czech Republic, Bosnia, Croatia, Greece, Hungary, Macedonia, Romania, Serbia and Turkey, as well as France, Italy, Germany and Poland have reported supply disruptions.