OSLO, Aug. 6 (Xinhua) -- The Russian Navy announced large-scale drilling activity off the coast of Northern Norway between Aug. 14 and 17, and three U.S. surveillance aircraft arrived in Norway to keep an eye on the drill, Norway's public broadcaster NRK reported on Tuesday.
The three U.S. P-8A Poseidon surveillance aircraft were stationed on the northern island of Andoya.
"A larger number of naval vessels are on their way from Russia to the areas where the Russians have announced that they will be practicing," Sigurd Tonning-Olsen, press officer of Norwegian Armed Forces, told NRK.
According to the Norwegian Armed Forces, Russia notified NOTAM (Notice to AirMen) in four areas, which is "an unusually large number", and where Russian navy vessels want to execute drilling activities.
"There is no need to be worried, but we are watching closely," said Major General Lars Christian Aamodt at the Norwegian Joint National Headquarters.