In principle, only sovereign states can become UN members. But, India gained UN membership before its independence. India is one among the original members of the United Nations and signed the Declaration of the United Nations in 1944 at Washington DC.
India was not the only member to gain membership before independence. Belarus, the Philippines, and Ukraine too got membership similarly.
Though India, Canada, South Africa, New Zealand and Australia were all British colonies, they were given independent seats in the United Nations General Assembly. It was Sir Arcot Ramaswamy Mudaliar, who signed the UN Charter on behalf of India during the San Francisco Conference on 26 June, 1945.
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