What is the ruling on obtaining the citizenship of a disbeliever state and swearing an oath of loyalty to that state in order to obtain citizenship?

Question:
May Allah reward you, Honorable Shaykh. These are questions regarding emigration to the lands of the disbelievers. This questioner says: In the lands of disbelief, if a man wants to obtain citizenship, he swears an oath that he will be loyal to this disbeliever country. Is it permissible for him to do that? And what is the ruling on his obtaining the citizenship of that state?

Answer:
It is not permissible for him to take the citizenship of the disbelievers, because if he takes it, he submits to their disbelieving systems, and they force him to do so because he has become one of their subjects. So it is not permissible for him to acquire the citizenship of the disbelievers. But if he is compelled to reside there, he resides while maintaining his religion and does not enter under their citizenship; he remains with his citizenship in the lands of the Muslims.