UPDATE 1-Gazprom CEO says gas supply deal with China may affect European prices

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ST PETERSBURG, Russia, May 23 (Reuters) - Russia's landmark deal to supply gas to China may affect prices in Europe, the chief executive of Russia's state company Gazprom Alexei Miller said on Friday.

Russia and China signed a 30-year gas supply contract, worth a total of more than $400 billion, earlier this week during President Vladimir Putin's visit to the country.

Neither side disclosed the price, but industry sources said it was between $350-$380 per thousand cubic meters, similar to what most European utilities pay under discounted long-term contracts signed in the last two years.

Putin said this week the formula was similar to the European price tied to the market value of oil and oil products.

Gazprom has yet to build a pipeline to bring 38 billion cubic meters of gas to China from 2018. Russia and China have agreed on a $25 billion prepayment under a supply deal, Alexander Medvedev, chief executive of Gazprom Export, said on Friday.

(Reporting by Vladimir Soldatkin; Writing by Lidia Kelly; editing by Katya Golubkova)