WASHINGTON, August 14 (RIA Novosti) - The United States government said its four-week expedition to the Arctic, an area estimated to contain 25% of the global oil and gas reserves, is "dedicated to enhancing economic security and national safety."

Apart from the U.S., the energy-rich area on the Arctic seabed is being challenged by other countries such as Denmark, Norway, Russia and Canada that have territory inside the Arctic Circle. Under international law, the five countries are entitled to claim only a 200-mile economic zone around their coastlines.

The National Oceanic and Atmospheric Administration (NOAA), funded by the U.S. Department of Commerce, said the Coast Guard cutter Healy, which left the port of Seattle (Washington) August 6, and a team of scientists from the University of New Hampshire's Joint Hydrographic Center and the National Science Foundation would start exploring the Arctic seafloor August 17.

"Scientists will explore this poorly known region to better understand its morphology and the potential for including this area within the United States' extended continental shelf under the United Nations Convention on Law of the Sea," the NOAA said.

The U.S. expedition follows a Russian Arctic trip in late July. Two Russian mini-submarines dove 14,000 feet below the Pole and planted a titanium Russian flag on the seabed. Russian scientists took rock and fauna samples to back the country's claim to the territory, which Moscow says is a continuation of its continental shelf starting from Siberia.

The NOAA said the Healy expedition would be the third in the past four years. The NOAA has also urged the Senate to pass legislation claiming the territory and securing future access to those resources.

The Associated Press agency said earlier that a State Department official, who is also a geographer and a member of the working group for the continental shelf, would join the expedition.

Last week, the New York monthly Harper's Magazine published a report saying a U.S. government working group had been exploring the Arctic seafloor since 2003 to back a U.S. claim to the shelf, which Washington plans to file after the Senate ratifies the UN Convention on Law of the Sea.