Extending permit timelines for drilling in the Gulf of Mexico may affect long-term deepwater development in the region, according to a Wood Mackenzie study sponsored by the American Petroleum Institute (API).

About one-third of US deepwater production would be uneconomic, leading to less energy production, investment and government revenues, the study revealed.

Almost 680,000 barrels of oil equivalent production a day in the Gulf of Mexico could be at risk in 2019, according to the report’s figures.

The study also projects that between 2011 and 2022, investments worth $70bn and government revenues worth $18bn could be at risk.