IAS exams and non-citizen Indians

The candidate must be a citizen of India to be eligible for the Indian Administrative Service (IAS) and the Indian Police Service (IPS), for other services, a candidate must be either:
a citizen of India,
or a subject of Nepal,
or a subject of Bhutan,
or a Tibetan refugee who came over to India before 1st January, 1962 with the intention of permanently settling in India,
or a person of Indian origin who has migrated from Pakistan, Burma, Sri Lanka, East African countries of Kenya, Uganda, the United Republic of Tanzania, Zambia, Malawi, Zaire, Ethiopia and Vietnam with the intention of permanently settling in India.
Provided that a candidate belonging to categories (c), (d), (e) and (f) shall be a person in whose favour a certificate of eligibility has been issued by the Government of India.
Provided further that candidates belonging to categories (c), (d) (e) and (f) above will not be eligible for appointment to the Indian Foreign Service
Note: A candidate in whose case a certificate of eligibility is necessary is eligible to take the examination but the offer of appointment may be given to only those candidates who have submitted the necessary eligibility certificate issued to him/her by the Government of India.

Note: The Candidates applying for the Civil Service Examination should ensure that they fulfil all eligibility conditions and criteria for admission to examination. Their admission to all the stages of the examination will be purely provisional subject to satisfying the prescribed eligibility conditions. Mere issue of admission certificate to the candidate will not imply that his/her candidature has been finally cleared by the UPSC. UPSC take up verification of eligibility conditions with reference to original documents only after the candidate has qualified for Interview/ Personality Test.