The president of Mexico (Spanish: Presidente de México), officially known as the President of the United Mexican States (Spanish: Presidente de los Estados Unidos Mexicanos), is the head of state and head of government of Mexico. Under the Constitution of Mexico, the President is the chief of the executive branch of the federal government and is the commander in chief of the Mexican Armed Forces. The current president is Andrés Manuel López Obrador, who took office on 1 December 2018. The office of the president is considered to be revolutionary, in the sense that the powers of office are derived from the Revolutionary Constitution of 1917. Another legacy of the Mexican Revolution is the Constitution's ban on re-election. Mexican presidents are limited to a single six-year term, called a sexenio. No one who has held the post, even on a caretaker basis, is allowed to run or serve again. The constitution and the office of the President closely follow the presidential system of government.