Portugal is governed under the constitution of 1976 as amended. The president, who is the head of state, is elected by popular vote to a five-year term and is eligible for a second term. The premier, who is appointed by the president and must have support of the legislature, is the head of government. In addition, a Council of State acts as a consultative body to the president and consists of representatives from the political parties, a military defense board, and a constitutional tribunal. The unicameral legislative body is the 230-seat Assembly of the Republic, whose members are elected to four-year terms. The Socialist party and the Social Democratic party are the two major political parties. Administratively, Portugal is divided into 18 districts and two autonomous regions (the Azores and Madeira Islands).