Around 300 people are stranded in Svalbard, after the North Pole was closed to visitors for the first time in 18 years over tensions between Russia and Ukraine.

The seasonal camp of Barneo, from where explorers are allowed to travel to the North Pole for a brief period annually, is privately operated by Swiss and Russian entities.

But the planes due to fly adventurers to the camp, established temporarily on a floating ice cap close to the North Pole, were Ukrainian.

The camp was scheduled to open on April 1, but the Ukrainian pilots and crew were not given permission to fly, a move linked to rumbling discontent over the war in eastern Ukraine, according to local media reports.

By the time a replacement plane from Canada was scrambled, weather conditions were no longer stable enough to guarantee enough time to bring visitors to the ice floe and back.