The Unite Mexican States (Spanish: Estados Unidos Mexicanos (help·info)), or commonly Mexico (IPA: /ˈmɛksɪkoʊ/) (Spanish: México (help·info) Spanish pronunciation: [ˈmexiko]), is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the North Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of Mexico. The United Mexican States is a federation comprising thirty-one states and a federal district, the capital Mexico City, whose metropolitan area is one of the world's most populous.