Exxon gets access to nearly 1.5 million acres in the Gulf of Mexico. The U.S. Interior Department estimates the area, Alaminos Canyon, contains as much as 172 million barrels of oil and 304 billion cubic feet of natural gas.
The transboundary area was opened by congressional agreement in December. Through it, U.S. companies agree voluntarily to develop the area jointly with Mexican energy company Petroleos Mexicanos.
"These leases represent a significant step forward in U.S.-Mexico cooperation in energy production and pave the way for future energy and environmental collaboration," U.S. Interior Secretary Sally Jewell said in a Saturday statement.
The Interior Department's Bureau of Ocean Energy Management sold the three leases areas in March for a total of $21.3 million.
The Sierra Club protested the move to open the area up to exploration and production, arguing energy companies have enough work on their hands.
There was no comment from Exxon on Jewell's announcement.