Three US B-2 Spirit stealth bombers flew an extended sortie over the Norwegian Sea, a strategically important space in the increasing tensions with Russia.

The B-2s, part of the 509th Bomb Wing from Whiteman Air Force Base in Missouri, also made their first visit to Iceland last month and flew with Royal Air Force F-35s, the first time B-2s had flown with foreign F-35s.

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In a clear message to Russian forces, three US B-2 Spirit stealth bombers flew an extended sortie over the Arctic Circle for the first time on Sept. 5, the Air Force's 509th Bomb Wing confirmed to Insider.

"This familiarization was the B-2's first mission this far north in the European theater," according to a Facebook post from the US Air Forces in Europe and Air Forces Africa.

Details about the sortie over the Norwegian Sea are scarce, but the aircraft involved completed a night refueling over the Arctic Circle as part of Bomber Task Force Europe. In March, Norway accused Russia of jamming its GPS systems and interfering in encrypted communications systems.

"Training outside the U.S. enables aircrew and Airmen to become familiar with other theaters and airspace, and enhances enduring skills and relationships necessary to confront a broad range of global challenges," US Air Force spokesman Capt. Christopher Bowyer-Meeder told Insider.

Read More: Stunning photos show US Air Force B-2 stealth bombers training with British F-35 fighters for the first time

The B-2s are part of the 509th Bomb Wing from Whiteman Air Force Base in Missouri. They are deployed to Royal Air Force Base Fairford near Gloucestershire, England where last month they flew with non-US F-35s for the first time. RAF Fairford is the forward operating location for US Air Force in Europe's bombers.

Four KC-135 Stratotanker aircraft from the 100th Air Refueling Wing stationed at RAF Mildenhall joined the B-2s on the mission over the Norwegian Sea.

A spokesperson from the 509th Bomb Wing told Insider that no other NATO aircraft were involved in the mission, and the bombers did not have any ammunition on board.

Last month, the B-2 also made its very first visit to Iceland, establishing the Air Force's presence in a region Russia considers its dominion. Iceland's Keflavik Air Base was established during the Cold War as a deterrent to the Soviet Union, and the B-2s' brief stopoff there demonstrated its ability to operate in cold-weather conditions.

In the past year, US forces have completed several missions from the region to deter Russian aggression against NATO allies, including B-52 training near the Crimean Peninsula, which Russia forcibly took in 2014. That aggression kicked off the European Deterrance Initiative to ensure quick reaction to threats and assure NATO allies of the US's commitment to defense.