However, a person who acquires a foreign citizenship by applying for it may lose U.S. citizenship. In order to lose U.S. citizenship, the law requires that the person must apply for the foreign citizenship voluntarily, by free choice, and with the intention to give up U.S. citizenship. See, you go to USA, get gren card, then write citizenship test, then before taking up US citizenship you MUST lose your Nepali citizenship. You surrender nepalese citizenship then only you become US citizen. Now if you go back and apply for Nepali citizenship, you applied voluntarily and in ehich case by law you automatically lose US citizenship. Sorry DUAL citizenship is not allowed. Dual citizenship holders are still there... but they are old people who did so long time ago.. they banned that after 1970s or 1980s somewhere, I am not sure.