'Maundy III' was a British unrealised operation, otherwise known as 'Dundee' (ii), by the Special Operations Executive to lay mines in the area to the north of Florø in German-occupied Norway (16 April 1944 onward).

Alternative tasks were limpet-mine attacks on shipping in the Gulenfjord, the introduction of explosive charges into cases of salt herrings, and sabotage of the automatic navigation lights in the fjord. Despite four attempts, the first on 16 April, bad weather and poor conditions meant that the operation did not take place.