Mexico’s state-owned oil company Petroleos Mexicanos has announced that it will offer a farm-out arrangement to private firms to join in the exploration of a deepwater field in the Gulf of Mexico.

According to the Associated Press report, it would be the first time that PEMEX has formed an association with a private firm for deepwater drilling. PEMEX director Jose Antonio Gonzalez, quoted in the AP report, called it “a watershed moment in PEMEX’s history.

” The Trion field, located in the Perdido belt just 25 mi (40 km) south of the US maritime border, is estimated to hold the equivalent of 480 MMbbl in proved, potential, and possible oil and gas reserves. PEMEX officials say that the offer will be put up for bid in coming days, and a winner will be announced on Dec. 5. Gonzalez did not specify what compensation the farm-out scheme would involve. Officials estimate it will take $11 billion in investments to develop the field in waters about 8,200 ft (2,500 m) deep.