When Germany invaded the Soviet Union in Operation Barbarossa in June 1941, the situation changed; British Communists became fervent supporters of the war. For the rest of the war, the paper was a strong supporter of the British war effort, and campaigned to organise a "Second Front" in Europe to assist the Soviet Union. The government's ban on the "Daily Worker" was lifted in September 1942, following a campaign supported by Hewlett Johnson, the Dean of Canterbury, and Professor J. B. S. Haldane. A "Lift the ban" conference at Central Hall, Westminster on 21 March 1942 was attended by over 2,000 delegates. A key part of the campaign was to secure Labour Party support (Herbert Morrison was a fierce opponent of the "Daily Worker"). On 26 May 1942, after a heated debate, the Labour Party carried a resolution declaring the Government must lift the ban on the "Daily Worker".