A軍集団
Manstein took no more part in the planning and returned to east Germany. Halder had to revise the plan again, which became N°4, . The new plan conformed to Manstein's thinking in that Army Group A would provide the main thrust of the invasion through the Ardennes in southern Belgium. After crossing the Meuse River between Namur and Sedan, Army Group A would turn north-west towards Amiens, as Army Group B executed a feint attack in the north, to lure the Allied armies forward into Belgium and pin them down.