The company will spend $544m to develop the Shenzi North, which represents the first development phase of Greater Wildling.
The project will involve adding two new wells and subsea equipment to establish a new drill centre with a production capacity of nearly 30Mboe per day.
BHP operates Shenzi North, along with a 72% stake in the project. Repsol owns the remaining 28% interest and is expected to make a final investment decision (FID) later this year.
The production from the deepwater field is expected to begin in 2024.
Separately, the BHP board also approved $258m for the Trion oil project.
The funding will help the project to advance to the front-end engineering design (FEED) phase and carry out engineering studies, commercial arrangements and execution planning to conduct FID next year.
BHP holds a 60% participating interest in and operatorship of blocks AE-0092 and AE-0093 hosting the Trion discovery. The other stakeholder is Pemex Exploration & Production Mexico.
BHP petroleum operations president Geraldine Slattery said: “Both Shenzi North and Trion are strong growth assets for our business, providing attractive returns from relatively low carbon intensity resources.
“Shenzi North is aligned with the petroleum strategy to unlock and deliver further growth options in this key Gulf of Mexico heartland.
“This Board decision also marks an important milestone in advancing the Trion development as we continue to work with our partner PEMEX towards a final investment decision in calendar year 2022.”
Last month, Bloomberg reported that BHP is considering divesting oil and gas operations. The review follows increasing investor pressure on the company to reduce its carbon footprint.