Iceland allowed US nuclear-powered submarines to refuel off its coast for the first time on Tuesday, boosting surveillance in the North Atlantic, a zone of contact with Russian submarines, AFP and News.ro reported.

Although part of NATO, the small Scandinavian nation has previously refused such visits because of its opposition to energy and nuclear weapons.

“This decision by the Ministry of Foreign Affairs is part of the Icelandic government’s policy to support allied surveillance and response capabilities in the North Atlantic,” the Reykjavik government said in a statement.

However, refueling will not take place in Icelandic ports, but “several kilometers from the coast.”

Another condition is that the submarines in question do not have nuclear weapons on board.

“The first submarine will visit in the near future,” the Icelandic government said.

The Atlantic area around Iceland is known as a strategic submarine zone, meeting Russian ships coming from the Barents Sea and Western submarines coming from the North Sea or the US.

A country with a population of 370,000, Iceland has been a founding member of NATO since 1949, but is notable for not having an army. It has only one Coast Guard unit.