However, a South African citizen who by a formal and voluntary act acquires the citizenship of another country, automatically loses his or her South African citizenship unless they apply for, and receive permission to retain their South African citizenship before acquiring the citizenship of the new country. A naturalized citizen however cannot apply for such a retention under the law. There is not a specific requirement to do so if residing in South Africa or if the claim is inevitable such as a dual Zimbabwean-South Africa possessing the Right of Abode in the UK then registering as a British Citizen but it is advised by the Department of Home Affairs. The Home Affairs has the responsibility to decide whether or not the application would meet by a Voluntary or Formal and decide on whether or not it is necessary to give that permission. If a South African Citizen wishes to restore a previously lost Citizenship (usually by birth in another country or of their ancestors) due to acquiring Citizenship of another country, for instance citizenship of one of the territories that the Soviet Union controlled, then it is not a Voluntary or Formal Act when applying and retention of South African Citizenship is not necessary.