Deep in the Oman desert lies one of BP's more lucrative projects, a mass of steel pipes and cooling towers that showcases the British energy giant's pioneering natural gas extraction technology.

The facility earned BP PLC more than $650 million in profits in 2019, according to financial filings. Yet the oil major agreed to sell a third of its majority stake in the project earlier this year. The deal exemplifies a larger strategy to liquidate fossil-fuel assets to raise cash for investments in renewable energy projects that BP concedes won't make money for years.

BP's big bet is emblematic of the hard choices confronting Big Oil. All oil majors face mounting pressure from regulators and investors worldwide to develop cleaner energy and divest from fossil fuels, a primary source of greenhouse-gas emissions that cause global warming. That scrutiny has increased since early August, when the United Nations panel on climate change warned in a landmark report that rising temperatures could soon spiral out of control.