In 1940 the Polish Highland Brigade took part in the Battle of Narvik (Norway), and two Polish divisions participated in the defense of France, while a Polish motorized brigade and two infantry divisions were in process of forming. A Polish Independent Carpathian Brigade was created in French-mandated Syria. The Polish Air Force in France had 86 aircraft with one and a half of the squadrons fully operational, and the remaining two and a half in various stages of training. Although many Polish personnel had died in the fighting or had been interned in Switzerland following the fall of France, General Sikorski refused French Marshal Philippe Pétain's proposal of a Polish capitulation to Germany. On 19 June 1940, Sikorski met with British Prime Minister Winston Churchill and promised that Polish forces would fight alongside the British until final victory. Sikorski and his government moved to London and were able to evacuate many Polish troops to Britain. After the signing of a Polish-British Military Agreement on 5 August 1940, they proceeded to build up and train the Polish Armed Forces in the West. Experienced Polish pilots took part in the Battle of Britain, where the Polish 303 Fighter Squadron achieved the highest number of kills of any Allied squadron. Sikorski's Polish forces would form one of the most significant Allied contingents.