Sri Lanka

(1) There shall be one status of citizenship known as “the status of a citizen of Sri Lanka”.
(2) A citizen of Sri Lanka shall for all purposes be described only as a “citizen of Sri Lanka”, whether such person became entitled to citizenship by descent or by virtue of registration in accordance with the law relating to citizenship.
(3) No distinction shall be drawn between citizens of Sri Lanka for any purpose by reference to the mode of acquisition of such status, as to whether acquired by descent or by virtue of registration.
(4) No citizen of Sri Lanka shall be deprived of his status of a citizen of Sri Lanka, except under and by virtue of the provisions of sections 19, 20, 21 and 22 of the Citizenship Act:
Provided that the provisions of sections 23 and 24 of that Act shall also be applicable to a person who became entitled to the status of a citizen of Sri Lanka by virtue of registration under the provisions of section 11, 12 or 13 of that Act.
(5) Every person who immediately prior to the commencement of the Constitution was a citizen of Sri Lanka, whether by descent or by virtue of registration in accordance with any law relating to citizenship, shall be entitled to the status and to the rights of a citizen of Sri Lanka as provided in the preceding provisions of this Article.
(6) The provisions of all existing written laws relating to citizenship and all other existing written laws wherein reference is made to citizenship shall be read subject to the preceding provisions of this Article. (Art. 26)

Immigration and Emigration and Citizenship
This would include –
(a) Citizenship, Naturalization and Aliens;
… (Ninth Schedule, List II, Reserved List)