An alleged Russian spy whale found by Norwegian fishermen this week is refusing to leave their port city, in what appears to be a high-profile defection.

Norwegian Directorate of Fisheries spokesman Jorgen Ree Wiig has told The Washington Post that the beluga “was the first thing I saw outside of the window” of his patrolling ship in the morning.

Speaking from the city of Hammerfest, he said the whale had moved only about 25 nautical miles in the past week and appeared to enjoy being close to humans. That, he said, was strange behaviour for a beluga.

The whale was first reported by fishermen, who saw it swimming around their boat in Arctic Norway last week. It was wearing a tight harness with “Equipment St Petersburg” written on the strap, and a camera attachment.

Fisherman Joar Hesten jumped into the frigid water to remove the harness, which was later handed to Norway’s special police security agency.

Audun Rikardsen, a professor at the Department of Arctic and Marine Biology at the Arctic University of Norway in Tromsoe, said he believed “it is most likely that Russian Navy in Murmansk” was involved.

The find has triggered fresh speculation about a sea mammal special operations program that the Russian navy is believed to have pursued for years. According to The Washington Post, the Russian Defence Ministry has denied its existence, but the same ministry did publish a 2016 ad seeking three male and two female bottlenose dolphins and offering to pay $24,000.

Russia has major military facilities in and around Murmansk, on the Kola Peninsula, in the country’s far north-west.

While the idea of putting sea mammals to work for the military might seem far-fetched, there is actually a precedent. According to The Washington Post, the US spearheaded such a program in the 1950s.

The US Navy has its own dolphin and sea lion recruits, which are used to find sea mines, retrieve objects from the ocean floor and gather intelligence for military divers.

Meanwhile, Norwegian officials are wondering what to do with their beluga defector. Mr Wiig said one option was to transport it to a sanctuary in Iceland – about 2000 kilometres away.

That proposal, he said, might increase chances of “the survival of the whale”.

-with agencies