Fatwa ID: 04054
Answered by: Alimah Sabrina Saidova
Is it permissible to take Italian citizenship and saying the following oath: "I swear to be faithful to the Republic and to observe the Constitution and the laws of the State"?
بِسْمِ اللهِ الرَّحْمنِ الرَّحِيْم
In the name of Allah, the Most Gracious, the Most Merciful
The Prophet (peace be upon him) has said: “Listening and obeying [the ruler] is necessary upon a Muslim in what he likes and dislikes, as long as he is not ordered to carry out a sin. If he is commanded to commit a sin, then there is not adherence, and neither is their obedience.” 
Based upon such Hadith, we as Muslims are required to abide by the laws of the land and as long as we’re not commanded to commit sinful acts. Thus, taking such an oath is permissible rather one must be conscious of upholding the oath they make as it’s an Amanah (trust) one is making, and breaking the trust has been classified as a sign of a hypocrite in a Hadith.
Only Allah knows best
Answered by Alimah Sabrina Saidova
Checked and approved Mufti Mohammed Tosir Miah
Darul Ifta Birmingham
 Sahih al-Bukhaari 2/1057, Qadeemi Kutub Khana