The movement included members of the Independent Labour Party, the British Socialist Party, Workers Socialist Federation, and the Herald League, who wanted to show international workers’ solidarity with their Russian comrades. Where other attempts at cross-factional unity had failed, the Hands Off Russia! campaign proved to be a powerful galvaniser of British left-wing sympathisers. It really got going in January 1919 when a National Committee for the Hands off Russia! campaign was elected at a conference in London. Many of the groups and individuals who congregated under the umbrella of Hands Off Russia! later went on to form the Communist Party of Great Britain in August 1920.

http://armingallsides.on-the-record.org.uk/case_studies/hands-off-russia/