'Lemsford' was a British unrealised deception by the London Controlling Section designed to induce Bulgaria to drop out of the war or bring all her forces back into the homeland, and also to persuade the Germans to reinforce the defences of Bulgaria (October 1943).

The plan was based on passing to the Bulgarians and German false information about the Allied intention to bomb Bulgaria into military, political and economic collapse, to drop large numbers of saboteurs to decimate Bulgaria’s industries and infrastructure, and to make an eventual assault on Sofia, the Bulgarian capital, with airborne forces.