The Laptev Sea shelf underneath Russia's Arctic waters holds an estimated 9.3 billion barrels of oil equivalent and 32.3 trillion cubic feet of natural gas in undiscovered resources, the U.S. Geological Survey said Friday.

The USGS is currently reassessing its estimation of the petroleum resource base in the Arctic circle based on new data, region by region.

Based on USGS's last assessment in 2000, the entire Arctic region was previously thought to contain almost 25% of the world's undiscovered oil and natural gas, but harsh conditions have thus far prevented mass development.

Of the 9.3 billion barrels of oil equivalent estimated, the USGS believes 3.07 billion barrels could be crude.

The USGS has said that knowing the potential resources of the Arctic - an area of tremendous resource potential, environmental sensitivity, technological risk and geological uncertainty - is critical to developing energy policies for future energy supplies to the U.S. and the world.

In late August, the USGS revised downward its estimate of resources off the northeastern shore of Greenland.

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