Gazprom Neft , the oil arm of Russian gas giant Gazprom said on Tuesday that a state subsoil commission has increased the oil reserves valuation of eastern offshore oilfield Neptun to almost 416 million tonnes from the initial estimates.

Neptun, located near the Sakhalin island in the Pacific Ocean, was Gazprom Neft’s largest oil discovery last year. The company said reserves had been raised by 1.6 times the previous estimate, according to Reuters.

Russian oil companies have increased oil development in the country’s distant regions, such as East Siberia and the Far East, as traditional oilfields, located in Western Siberia, have become increasingly depleted.

“Neptun field has become one of the largest of Gazprom Neft’s assets by reserve volumes,” Alexander Dyukov, Gazprom Neft’s head, said in a statement.

“The Far East will be a new strategically important region of our activity for many years ahead, which will allow our company to work more actively on the Asia Pacific region’s markets,” he said.