MOSCOW

IN one of the more unusual rescue operations in the history of

Arctic navigation, a Soviet icebreaker rammed a 15-mile path through thick ice last month to free thousands of trapped white beluga whales.

The saga of the whales, known in Russia as belukhas or polar dolphins, made for some of the winter's more suspenseful reading as the icebreaker Moskva raced against time and plunging temperatures to reach the whales before they suffocated or starved in shrinking pools of open water. Like other seafaring mammals, Belugas must rise to the surface to breathe.

Soviet television's first film report a week ago on what came to be known as ''Operation Belukha'' showed masses of the 10-foot-long white whales struggling for breathing room in a small pool of open water while the giant Moskva ploughed ponderously toward them through the seemingly endless expanse of ice.

The operation recalled the drama in the fall of 1983 when a flotilla of icebreakers struggled to break through thick pack ice to some 20 freighters and tankers that became trapped in the Arctic Ocean. One of the ships was crushed and sunk by the grinding ice floes before the icebreakers succeeded in breaking a path for them to the open sea.