Section 83 of Code of Civil Procedure 1908 "When aliens may sue"
Alien enemies residing in India with the permission of the Central Government, and alien friends, may sue in any Court otherwise competent to try the suit, as if they were citizens of India, but alien enemies residing in India without such permission, or residing in a foreign country, shall not sue in any such court.
Explanation-Every person residing in a foreign country, the Government of which is at war with India and carrying on business in that country without a licence in that behalf granted by the Central Government, shall, for the purpose of this section, be deemed to be an alien enemy residing in a foreign country.
Section 84 of Code of Civil Procedure 1908 "When foreign State may sue"
A foreign State may sue in any competent Court:
Provided that the object of the suit is to enforce a private right vested in the Ruler of such State or in any officer of such State in his public capacity.