Complex sentence: Both administrations--the Fatah government in Ramallah and the Hamas government in Gaza--regard themselves as the sole legitimate government of the Palestinian National Authority, however the international community and Palestine Liberation Organization recognize the Ramallah administration as the legitimate government.
Split into simpler sentences: Both administrations--the Fatah government in Ramallah and the Hamas government in Gaza--regard themselves as the sole legitimate government of the Palestinian National Authority. The international community and Palestine Liberation Organization, however, recognize the Ramallah administration as the legitimate government.