(CNN) -- The United States and Mexico agreed Monday to work cooperatively on exploring and developing oil and natural gas reserves along their maritime border.
U.S. Secretary of State Hillary Clinton and Interior Secretary Ken Salazar attended the signing of the pact known as the Transboundary Agreement in Los Cabos, Mexico, with Patricia Espinosa, the Mexican foreign relations minister.
The agreement requires approval by the U.S. and Mexican national legislatures.
According to a statement by the U.S. Interior Department, the agreement will open up almost 1.5 million acres of U.S. outer continental shelf to exploration and development of oil and natural gas reserves.
The area, roughly the size of Delaware, is estimated by the Interior Department's Bureau of Ocean Energy Management to contain up to 172 million barrels of oil and 304 billion cubic feet of natural gas, the department statement said.
"This agreement makes available promising areas in the resource-rich Gulf of Mexico and establishes a clear process by which both governments can provide the necessary oversight to ensure exploration and development activities are conducted safely," Salazar said in the statement.
The Transboundary Agreement creates a framework for Mexico's state-owned Petroleos Mexicanos (PEMEX) to work with U.S. oil and gas companies in developing the maritime boundary area.
It follows the commitment last year by U.S. President Barack Obama and Mexican President Felipe Calderon to work out an agreement on developing the maritime border reserves.