The protestors floated a huge blue balloon with black spots they said symbolised the polluted Earth.

"Although Russia's trade is based on the export of oil products, safety requirements in production and transportation are low," organiser Anatoly Panfilov told Interfax.

Some 100 million tonnes of oil seep into the ground in the Western Siberian region of Russia alone, Panfilov said.

He further accused Russian companies of damaging oil wastage, extracting only 30 to 30 percent of proven reserves in many deposits.

"Oil magnates skim the cream and abandon the wells. They leave behind dead, oil-soaked ground," Interfax quoted Panfilov as saying.

Russian ecologists have warned that slack environmental protection standards have entailed serious deterioration in health and safety conditions in oil-production regions, and are calling for mandatory controls in subsequent development projects.

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