Original plans called for Saukko to be brought to the town of Lahdenpohja on Lake Ladoga by rail, but this was never implemented.

Saukko, accompanied by several motor torpedo boats, was towed by the gunboat Karjala to Koivisto on 7 December 1939.

Since hostilities had started before the Finnish Navy had a chance to lay defensive minefields outside their coastal forts, it was hoped that Saukko might be able to accomplish that task.

When the ice was finally broken, half of the air valves on Saukko were frozen, which nearly caused the boat to capsize when it tried to submerge to lay a minefield.

The submarine fired a torpedo but was forced to withdraw, without being able to observe results, by harassing Soviet patrol boats.