Russia has deployed tactical nuclear weapons-armed ships in the Baltic Sea for the first time in three decades, according to a Norwegian intelligence report released on February 13.

The vessels belong to Russia’s Northern Fleet, The New Voice of Ukraine reported earlier this week.

“The key part of the nuclear potential is on the submarines and surface ships of the Northern Fleet,” the Norwegian intelligence agency said.

“Tactical nuclear weapons are a particularly serious threat in several operational scenarios in which NATO countries may be involved.”

“It cannot be ruled out that a localised war could escalate into a wider conflict with direct military involvement of Russia, the United States, NATO, and Norway.” the report said.

Russian President Vladimir Putin has repeatedly threatened to use nuclear weapons amid its ongoing war in Ukraine, which NATO and Western leaders dismissed as blackmail.

According to Vilnius officials and intelligence agencies, Russia has previously deployed nuclear weapons to its exclave of Kaliningrad which borders Lithuania and Poland.