Mountbatten Plan (June 3 Declaration) of 1947: Partition, Radcliffe Line and the Independence Act Explained

On 3 June 1947, the British Viceroy Lord Louis Mountbatten announced a plan that decided the future of British India. Often called the June 3 Declaration or the Mountbatten Plan, it set out the terms on which power would be handed over to Indians and accepted the partition of the country into two independent dominions, India and Pakistan. The announcement was made through a radio broadcast that evening, in which Mountbatten was followed by Jawaharlal Nehru for the Congress, Muhammad Ali Jinnah for the Muslim League, and Baldev Singh for the Sikhs. The plan is a high-value topic in Modern Indian History for UPSC, SSC and State PCS aspirants, and 2026 marks its 79th anniversary.

Background: Why the plan was needed

Mountbatten reached Delhi on 22 March 1947 to take charge as Viceroy. He came with a clear instruction from British Prime Minister Clement Attlee: power had to be transferred to Indian hands by 30 June 1948 at the latest. He arrived in a country already torn by communal violence. The Calcutta killings of August 1946 had been followed by disturbances in Noakhali and Bihar, and trouble had spread to Bombay and other regions. Punjab too was sliding into conflict, with serious violence in Amritsar, Rawalpindi and nearby areas.

After studying the situation and holding talks in India and in London in mid-May 1947, Mountbatten concluded that the demand for a separate Pakistan could no longer be avoided. He then brought forward his Partition Plan on the evening of 3 June 1947.

What the June 3 Plan proposed

At its heart, the plan accepted the division of British India. Its main provisions were:

• The legislative assemblies of Punjab and Bengal would each vote on whether their province should be partitioned.
• The assembly of Sindh would decide whether to join India or Pakistan.
• Referendums would be held in the North-West Frontier Province (NWFP) and in the Sylhet district of Assam to decide their future.
• If partition took place, a Boundary Commission would mark out the new borders, especially in Punjab and Bengal.
• Two independent dominions, India and Pakistan, would be created, each with its own Constituent Assembly.
• The princely states had to join one of the two dominions.
• The date for the transfer of power was advanced from June 1948 to 15 August 1947.

The plan replaced an earlier idea known as the "Balkan Plan", under which each province could have chosen to join the existing Constituent Assembly, form a new group, or stay separate. The Congress strongly opposed this earlier idea because it could have broken India into many fragments.

The Radcliffe Line and the Boundary Commission

Because Punjab and Bengal voted for partition, the boundaries of the two new countries had to be drawn quickly. A Boundary Commission was set up under Sir Cyril Radcliffe, a British lawyer who had never visited India before. The border he marked out between India and Pakistan came to be known as the Radcliffe Line. It was announced only after 15 August 1947. The hurried division of Punjab and Bengal, along with uncertainty over which districts would fall on which side, contributed to confusion and to one of the largest mass migrations in history.

The Indian Independence Act, 1947

The June 3 Plan was given legal form by the Indian Independence Act, 1947, passed by the British Parliament and given royal assent on 18 July 1947. The Act set 15 August 1947 as the date for the creation of the two dominions of India and Pakistan. It ended British paramountcy over the princely states, leaving each free to join either dominion, and it made the Constituent Assemblies of the two dominions their respective legislatures with full law-making powers. Until new constitutions were framed, each dominion was to be governed under the Government of India Act, 1935, with suitable changes.

Why the Congress and the Muslim League accepted it

The Congress accepted the plan for several reasons. Leaders hoped that a quick transfer of power to an Indian government would help control the rising communal violence. Many also felt that a smaller but united India with a strong central government was better than a large India in which deep political disagreement could block effective governance. According to accounts of the period, leaders such as Sardar Vallabhbhai Patel came to see partition as unavoidable, while Nehru accepted it with great reluctance. Mahatma Gandhi, who was deeply opposed to division, eventually reconciled himself to the decision after his talks with Mountbatten. Maulana Abul Kalam Azad remained one of the strongest voices against partition within the Congress.

For the Muslim League, led by Jinnah, acceptance of the plan meant the creation of Pakistan, its central political demand. The League believed that a separate state was needed so that Muslims would not be politically sidelined. Even so, Jinnah was unhappy that Punjab and Bengal themselves were being partitioned, though he accepted the plan as a whole.

Aftermath

When journalists asked Mountbatten whether the plan would lead to a large movement of people, he said he personally did not expect it. In reality, the months that followed saw widespread violence and a massive migration of people across the new borders, marking partition as one of the most tragic chapters of the subcontinent's history.