What language is closest to Maltese?

The language closest to Maltese is Arabic, specifically the variety of Arabic known as Maghrebi Arabic, due to historical influences and the language's roots in Arabic. However, Maltese has also been significantly influenced by Italian and Sicilian, making it a unique blend of these languages. It is the only official language of the European Union derived from Arabic. Overall, while Arabic is the closest relative, Maltese is distinct in its own right.