charters contain no such prohibition, shall not be deprived of their right to vote for elective provincial officials. Section 13. Local government units may group themselves, consolidate or coordinate their efforts, services, and resources for purposes commonly beneficial to them in accordance with law. Section 14. The President shall provide for regional development councils or other similar bodies composed of local government officials, regional heads of departments and other government offices, and representatives from non-governmental organizations within the regions for purposes of administrative decentralization to strengthen the autonomy of the units therein and to accelerate the economic and social growth and development of the units in the region. AUTONOMOUS REGIONS Section 15. There shall be created autonomous regions in Muslim Mindanao and in the Cordilleras consisting of provinces, cities, municipalities, and geographical areas sharing common and distinctive historical and cultural heritage, economic and social structures, and other relevant characteristics within the framework of this Constitution and the national sovereignty as well as territorial integrity of the Republic of the Philippines. Section 16. The President shall exercise general supervision over autonomous regions to ensure that laws are faithfully executed. Section 17. All powers, functions, and responsibilities not granted by this Constitution or by law to the autonomous regions shall be vested in the National Government. Section 18. The Congress shall enact an organic act for each autonomous region with the assistance and participation of the regional consultative commission composed of representatives appointed by the President from a list of nominees from multi-sectoral bodies. The organic act shall define the basic structure of government for the region consisting of the executive department and legislative assembly, both of which shall be elective and representative of the constituent political units. The organic acts shall likewise provide for special courts with personal, family, and property law jurisdiction consistent with the provisions of this Constitution and national laws. The creation of the autonomous region shall be effective when approved by majority of the votes cast by the constituent units in a plebiscite called for the purpose, provided that only provinces, cities, and geographic areas voting favorably in such plebiscite shall be included in the autonomous region. Section 19. The first Congress elected under this Constitution shall, within eighteen months from the time of organization of both Houses, pass the organic acts for the autonomous regions in Muslim Mindanao and the Cordilleras.