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ST PETERSBURG, Russia, May 24 (Reuters) - President Vladimir Putin expressed concern on Saturday about threats by "radicals" in Ukraine to interrupt Russian natural gas supplies to Europe.
Russia caters for about 30 percent of Europe's gas needs, and around half of the gas is supplied via pipelines that go through Ukraine.
"We are seriously concerned about statements by Ukrainian radicals, their direct threats to interrupt the transit of gas. We hope that common sense somehow prevails there," Putin told a gathering of international oil and gas executives.
Russia's pipeline gas exporting monopoly Gazprom has threatened to halt deliveries to Ukraine on June 3 if Kiev does not pay for its gas in advance and does not start reducing its $3.5 billion gas debt.
It was not exactly clear which statements Putin was referring to.
Representatives of Russia, Ukraine and the European Union are expected meet on Monday in Berlin to discuss the situation. Ukraine has offered to pay $268.50 per 1,000 cubic metres of gas but Russia is demanding a price of $485.
Relations between Kiev and Moscow have deteriorated since the overthrow of Ukraine's pro-Moscow president in February and Russia's annexation of the Crimea region from Ukraine in March.
Reporting by Denis Pinchuk, Writing by Vladimir Soldatkin, Editing by Timothy Heritage