A marine propulsion system comprising: - a first portion and a second portion of a set of movable foils, wherein the first portion of the set of foils is movable in a first fore plane and the second portion of the set of foils is movable in a second aft plane, the first fore plane and the second aft plane being arranged parallel to each other, - a movement mechanism comprising a first conveyor coupled to the leading edges of the foils of the first portion and the second portion of the set of movable foils, the first conveyor moving around a first plurality of wheels to simultaneously control a motion of the first portion and the second portion of the set of foils along a closed first trajectory comprising a first direction and a second direction which is opposite to the first direction , and - a pitch mechanism coupled to the first portion and the second portion of the set of movable foils and configured to control a pitch angle (π) of the first portion and the second portion of the set of movable foils, the pitch mechanism comprising a second conveyor coupled to the trailing edges of the foils of the first portion and the second portion of the set of movable foils and moving around a second plurality of wheels along a closed second trajectory , wherein the pitch angle (π) of at least a part of the second portion of the set of foils is dependent on an incoming fluid flow (v x ), the motion of the second portion of the set of foils, and a flow (v ind ) induced by at least a part of the first portion of the set of foils, and wherein the pitch angle (π) of the first portion of the set of foils and the pitch angle (π) of the second portion of the set of foils is independently adjustable by means of a forward pitch control and an aft pitch control in order to provide optimum angles of attack for the respective foils , the pitch angle (π) of the first portion of the set of foils and the pitch angle (π) of the second portion of the set of foils being controllable by adjusting the distance between the first conveyor and the second conveyor either by sliding of the first plurality of wheels of the movement mechanism relative to the second conveyor or second plurality of wheels of the pitch mechanism , or by sliding of the second plurality of wheels of the pitch mechanism relative to the first conveyor or the first plurality of wheels of the movement mechanism such that non-symmetric forces in a transverse direction may be obtained depending on the pitch angles (π) of the first portion and the second portion of the set of movable foils in order to manoeuvre a ship. - a first portion and a second portion of a set of movable foils, wherein the first portion of the set of foils is movable in a first fore plane and the second portion of the set of foils is movable in a second aft plane, the first fore plane and the second aft plane being arranged parallel to each other, - a movement mechanism comprising a first conveyor coupled to the leading edges of the foils of the first portion and the second portion of the set of movable foils, the first conveyor moving around a first plurality of wheels to simultaneously control a motion of the first portion and the second portion of the set of foils along a closed first trajectory comprising a first direction and a second direction which is opposite to the first direction , and - a pitch mechanism coupled to the first portion and the second portion of the set of movable foils and configured to control a pitch angle (π) of the first portion and the second portion of the set of movable foils, the pitch mechanism comprising a second conveyor coupled to the trailing edges of the foils of the first portion and the second portion of the set of movable foils and moving around a second plurality of wheels along a closed second trajectory , wherein <EOS>