The Legislative power in the national government is vested in the Congress of the Philippines consisting of the Senate and the House of Representatives. The Senate consists of 24 elected members half of which are elected every three years. The term of office is six years, and senators cannot serve more than two consecutive terms. The House of Representatives is composed of not more than 250 members. The most of the representatives are elected from the legislative district in provinces, cities, and Metropolitan Manila area on the basis of a uniform and progressive ratio of their respective populations. The party-list representatives constitute 20% of the total number of representatives. They are elected through a party-list system of registered national, regional and sectoral organizations. Members of the House of Representatives shall be elected for a three-year term and shall not serve for more than three consecutive terms. The Philippine Congress is authorizes to conduct enquiries, to declare war and override a presidential veto with two thirds vote of both houses. All appropriate bills must originate in the House however the president is given a line-item veto over them. The bill may be passed into law by either House of the representatives or by the Senate after it has passed the three days reading and has been approved by the president. If the president takes no action on the bill for 30 day, it automatically approved and become law. If the president vetoes the bill, it returns to the house that passed it and will be subject for reconsideration. The Senate ratifies treaties by two-thirds vote. The constitution allows people to enact laws or approve or reject laws passed by Congress or local legislative bodies with a petition signed by at least 10% of all registered voters.