 On 2 June , the final plan was given by the Viceroy to Indian leaders : on 15 August , the British would turn over power to two dominions . The provinces would vote on whether to continue in the existing constituent assembly or to have a new one , that is , to join Pakistan . Bengal and Punjab would also vote , both on the question of which assembly to join , and on the partition . A boundary commission would determine the final lines in the partitioned provinces . Plebiscites would take place in the North @-@ West Frontier Province ( which did not have a League government despite an overwhelmingly Muslim population ) , and in the majority @-@ Muslim Sylhet district of Assam , adjacent to eastern Bengal . On 3 June , Mountbatten , Nehru , Jinnah and Sikh leader Baldev Singh made the formal announcement by radio . Jinnah concluded his address with " Pakistan <unk> " ( Long live Pakistan ) , which was not in the script . In the weeks which followed Punjab and Bengal cast the votes which resulted in partition . Sylhet and the <unk> voted to cast their lots with Pakistan , a decision joined by the assemblies in Sind and Baluchistan . 
