In Thailand, speakers of Southern Thai can be found from as far north as Prachuap Khiri Khan Province down to the border with Malaysia. Small numbers of speakers can be found in the Malaysian border states, especially Kedah, Kelantan, Penang, Perlis, and Perak. It is the primary language of Thais as well as of the ethnically Malay people on both sides of the Thai-Malaysian border in Satun and Songkhla provinces. Although numerous regional variations exist and there is no one standard, the language is most distinct near the Malaysian border, but all varieties remain mutually intelligible to each other. For economic reasons, many speakers of Southern Thai have moved to Bangkok and other Thai cities or to the Middle East, where many speakers share Islam as a professed religion.