Russia's Northern Fleet Tu-142 Bear and Il-38 May anti-submarine aircraft have tested new electronic equipment and precision-guided weapons over the Barents and Norwegian Sea, a Navy spokesman said on Thursday.

"Advanced onboard electronic equipment and weapon control systems were tested during the flights. The tests have shown their high effectiveness," Capt. 1st Rank Igor Dygalo said.

He added that at some stage of the flights, Russian aircraft were accompanied by NATO warplanes, stressing that all such flights are conducted strictly in accordance with international agreements and the norms of international law.

Russia resumed strategic bomber patrol flights over the Pacific, Atlantic, and Arctic oceans last August, following an order signed by then-president Vladimir Putin. Russian bombers have since carried out over 80 strategic patrol flights and have often been escorted by NATO planes.

Air Force commander, Col. Gen. Alexander Zelin said in April that Russia would drastically increase the number of strategic patrol flights over the world's oceans to 20-30 a month in the near future.

The Arctic is becoming an area of increasing international focus due to the potentially large deposits of natural resources, including oil and natural gas, located there.