WASHINGTON (Reuters) -- Two nuclear-powered Russian attack submarines have been patrolling off the eastern seaboard of the United States in the first mission of its kind so close to shore in nearly a decade, U.S. officials have said.
The Pentagon said it was not alarmed by the maneuvers, carried out by what officials described as Soviet-designed Akula-class submarines in international waters as little as 320 kilometers off the coast.
The Russian operation comes at a time when U.S. President Barack Obama is pushing to "reset" relations between the two former Cold War rivals.
Pentagon press secretary Geoff Morrell said Obama saw that rivalry as "long passed" and that Washington was keeping an eye on the two vessels.
"So we don't look at this action and automatically see threatening motives," Morrell said. "We view this, we are mindful of it, we watch it, but we do not assign motives that we don't believe are there."
He said the Russian vessels were free to operate in international waters. "It doesn't cause any alarm within this building [the Pentagon].... It doesn't pose any threat," Morrell added.
Akula is the NATO code name for the Nerpa submarine, which has been in service since the mid-1980s. They are armed with torpedoes, cruise missiles, and can carry underwater missiles.
Morrell said the United States did not know specifically what the vessels were doing. But Pentagon officials said the submarine mission appeared to be part of efforts by Moscow to show a greater military presence around the world.
"Clearly there is an effort on their part to project force around the world, or at least to take excursions around the world," Morrell said. "No one here is overly concerned by it."
Cuba Port Call
One of the Russian submarines remained in international waters on August 4 a couple hundred kilometers off the coast of the United States, officials said.
The second sub made a port call in Cuba in recent days, "The New York Times" reported, citing Defense Department officials who spoke on condition of anonymity.
During the Cold War, the United States and Russia regularly sent submarines on secret missions near each other's coasts.
"It is the first time in roughly a decade that we've seen this kind of behavior," Morrell said.
Russia conducted a successful sea trial of the Nerpa last month in the Sea of Japan, according to the RIA news agency.
During testing of the submarine in November, 20 people died and 21 were hospitalized when the fire extinguishing system was turned on in error, releasing freon gas that asphyxiated the victims.
The accident, the worst to hit the Russian Navy since 118 sailors died in 2000 when the "Kursk" nuclear submarine sank in the Barents Sea, exposed the gap between the Kremlin's ambitions and its military capabilities.