Citizenship Act, 1955
8. Renunciation of citizenship
(1) If any citizen of India of full age and capacity, who is also a citizen or national of another country, makes in the prescribed manner a declaration renouncing his Indian citizenship, the declaration shall be registered by the prescribed authority, and, upon such registration, that person shall cease to be a citizen of India:
PROVIDED that if any such declaration is made during any war in which India may be engaged, registration thereof shall be withheld until the Central Government otherwise directs.
(2) Where 6[a person] ceases to be a citizen of India under sub-section (1) every minor child of that person shall thereupon cease to be a citizen of India:
PROVIDED that any such child may, within one year after attaining full age, make a declaration that he wishes to resume Indian citizenship and shall thereupon again become a citizen of India.