The Mujibnagar government made him ambassador-at-large, followed in August 1971 by the concurrent position of Advisor to the Acting President, a position he was to resign in January 1972 after the return to Bangladesh of Bangabandhu Sheikh Mujibur Rahman. He had a key role managing relations with the United States and India whilst heading the nascent country's diplomatic service. As the senior-most diplomat of the Bangladesh movement in the United Nations delegation under Justice Abu Sayed Choudhury which was in New York in September 1971 to lobby for the Bangladesh cause at the General Assembly, he played a vital role in the delegation's lobbying efforts. He was also in communication with other governments, such as the Nixon administration in the United States and also with Senators, Congressmen, and high officials in the US Administration, World Bank, and IMF; he had the advantage as well of being familiar with decision-makers and the decision-making process having served as a diplomat in Washington 20 years earlier. Former colleague Syed Muazzem Ali described him as a "soft-spoken and scholarly diplomat" who was exceptional in articulating the cause and whose contributions were invaluable. He was one of the first high officials to reach Dhaka after its liberation, and was quartered with other senior officials in Bangabhaban until January 1972. He was also the highest Bangladeshi official in Dhaka until the acting president and cabinet arrived after independence; on his arrival in Dhaka he was driven under escort from the airport, becoming the first civilian official to lay a wreath at the ruins of the Shaheed Minar, an act planned to mark the first presence of the government in Dhaka. Already the effective head of the incipient foreign service, he became Foreign Secretary at the end of 1971, playing a key role in formulating Bangladesh's foreign policy.The Bangladesh Liberation War, Mujibnagar Government Documents 1971, edited by Sukumar Biswas (Dhaka: Mowla Brothers, 2005)
