1. A Contracting State shall not deprive a person of its nationality if such deprivation would render him stateless.
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3. Notwithstanding the provisions of paragraph 1 of this Article, a Contracting State may retain the right to deprive a person of his nationality, if at the time of signature, ratification or accession it specifies its retention of such right on one or more of the following grounds, being grounds existing in its national law at that time:
(a) that, inconsistently with his duty of loyalty to the Contracting State, the person
(i) has, in disregard of an express prohibition by the Contracting State rendered or continued to render services to, or received or contin-ued to receive emoluments from, another State, or
(ii) has conducted himself in a manner seriously prejudicial to the vital interests of the State