UPDATE 1-Gazprom threatens to halt gas supplies to Ukraine

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MOSCOW, Feb 7 (Reuters) - Russia's gas export monopoly Gazprom (GAZP.MM: Quote, Profile, Research) threatened on Thursday to halt gas supplies to Ukraine over debts of $1.5 billion for previous deliveries.

Gazprom, the world's largest gas producer, supplies Europe with a quarter of its gas via Ukraine and Belarus. Previous pricing disputes have led to cuts in deliveries to Europe.

"If the Ukrainian side does not settle the problem on Monday, Gazprom will have to stop supplies of Russian gas to Ukraine," Gazprom spokesman Sergei Kupriyanov said in a statement.

He said Russia had increased gas supplies to Turkey, Greece and Ukraine since the beginning of the year after those countries faced lower deliveries from other suppliers.

"All our partners follow payments schedules and it is only with Ukraine that a paradoxical situation has emerged where it gets the gas it needs, but does not pay for it," he said. (Reporting by Tanya Mosolova; editing by Andrew Roche)