Reason Behind the Ninth Amendment Act, 1960
The government of West Bengal opposed to divide the territory of the Berubari Union even after the signing up of the Nehru-Noon Agreement between India and Pakistan. As a result, the matter was referred to the Supreme Court of India by the Union and Supreme Court held that the power of the Parliament to diminish the area of a state ( which is enumerated in the Article 3 of the Constitution) does not contain the cession of the Indian territory to a foreign country.
Therefore, an amendment needs to be made according to Article 368 of the Constitution so that Indian territory can be ceded to a foreign country. Hence, the Ninth Amendment Act, of 1960 was enacted.