On 20 December 1961, after military action, India acquired the territories of Goa, Daman and Diu and Dadra and Nagar Haveli which were under the territories of Portugal. The French territories of Puducherry, Karaikal, Mahé, and Yanam, were acquired under treaty of cession with France in 1954 (ratified by the French National Assembly in 1962). Previously, the French territory of Chandernagore had voted in a referendum to join the Indian Union in 1949. Sikkim was also merged with India and became a constituent state with effect from 16 May 1975. Some of the enclaves in the eastern part of India were also acquired under border agreements with Pakistan and Bangladesh.