The Attack on Mers-el-Kébir (3 July 1940) also known as the Battle of Mers-el-Kébir, was part of Operation Catapult. The operation was a British naval attack on French Navy ships at the base at Mers El Kébir on the coast of French Algeria. The bombardment killed 1,297 French servicemen, sank a battleship and damaged five ships, for a British loss of five aircraft shot down and two crewmen killed.
The combined air-and-sea attack was conducted by the after France had signed armistices with Germany and Italy that came into effect on 25 June. Of particular significance to the British were the seven battleships of the Bretagne , Dunkerque and Richelieu classes, the second largest force of capital ships in Europe after the Royal Navy. The British War Cabinet feared already that France would hand the ships to the , giving the Axis assistance in the Battle of the Atlantic. Admiral François Darlan, commander of the French Navy, promised the British that the fleet would remain under French control but Winston Churchill and the War Cabinet judged that the fleet was too powerful to risk an Axis take-over.
After the attack at Mers-el-Kébir and the Battle of Dakar, French aircraft raided Gibraltar in retaliation and the Vichy government severed diplomatic relations with the United Kingdom. The attack created much rancour between France and Britain but also demonstrated to the world that Britain intended to fight on. The attack is controversial and the motives of the British are debated. In 1979, P. M. H. Bell wrote that “The times were desperate; invasion seemed imminent; and the British government simply could not afford to risk the Germans seizing control of the French fleet… The predominant British motive was thus dire necessity and self-preservation”.
The French thought they were acting honourably in terms of their armistice with Nazi Germany and were convinced they would never turn over their fleet to Germany. Vichy France was created on 10 July 1940, one week after the attack and was seen by the British as a puppet state of the Nazi regime. French grievances festered for years over what they considered a betrayal by their ally. On 27 November 1942, the scuttling of the French fleet in Toulon foiled Operation Anton, a German attempt to capture the fleet.