'Guillemot' was a British operation by the Special Operations Executive to reinforce the 'Grebe' party and help undertake railway sabotage in German-occupied Norway (24 February/8 May 1945).

The two-man party of B. Sevendal and K. Bredsen, the 'Griffon' party and two Norwegian army officers were delivered by parachute on 24 February and assisted 'Grebe' in its operational area.