President Joe Biden has approved the Willow oil and gas drilling project in Alaska, which faced strong opposition from environmental activists.
The company behind the Willow project, ConocoPhillips, says it will create local investment and thousands of jobs.
But the $8bn proposal recently faced a torrent of online activism, with opponents arguing it should be halted over its climate and wildlife impacts.
Located on Alaska's remote North Slope, it has been the largest oil development in the region for decades and could produce up to 180,000 barrels of oil a day.
U.S. Bureau of Land Management estimates it will generate up to 278 million metric tonnes of CO2e over its 30-year lifetime - the equivalent of adding two million cars to U.S. roads yearly.