In the wake of Operation Iskra, which broke the German land blockade of Leningrad in the same month, Marshal G. K. Zhukov conceived a plan to encircle and destroy Army Group North: Operation Polyarnaya Zvezda. The first phase of the overall operation would be another attempt to cut off and eliminate the Demyansk salient. Zhukov finalized his plan during the week preceding the planned attack date of February 15. During a conference on February 10, he directed the commander of 1st Shock to transfer the forces of his right wing, including the 397th, and their tactical sectors to the adjacent 53rd Army However, in light of the encirclement and upcoming surrender of 6th Army at Stalingrad, on January 31 Hitler had authorized the evacuation of II Corps. Operation "Ziethen" began on February 17 before the delayed Soviet attack could get underway, and effectively short-circuited Zhukov's entire plan. Soviet ski troops of 34th and 53rd Armies were used to harass the retreating German units but they were unable to inflict any serious harm. Demyansk was abandoned on February 21 and by five days later most of the corridor was evacuated as well.