The Nepal Interim Government Act of 1951, put into effect after the Revolution of 1951, proclaims that all citizens have the right to form associations and unions. This is found under Section c of Article 17: Fundamental principles of law (Nepal 1951, 3)

Nepal. 1951 “The Interim Government of Nepal Act, 1951” Constitutionnet https://constitutionnet.org/sites/default/files/1951%20Constitution%20English.pdf