Notwithstanding anything contained in any other law for the time being in force, the provisions of the Registration of Foreigners Act, 1939, and the Foreigners Act, 1946, and of the rules and orders made thereunder shall apply to and in relation to any person who, or either of whose parents, or any of whose grand-parents was at any time a citizen or subject of any country at war with, or committing external aggression against, India or of any other country assisting the country at war with, or committing such aggression against, India, as they apply to and in relation to foreigners as defined for the purposes of those Acts.