The plant is expected to be operational in 2026 and will make polyethylene, a widely used plastic, the companies said in separate statements.

As the world charts a path towards net zero emissions, fossil fuels are still expected to be used in goods such as plastics.

Construction of the facility will start immediately and it will be owned by a joint venture called Golden Triangle Polymers Company, in which Chevron Phillips has a 51 percent equity stake and QatarEnergy holds the rest.

This is QatarEnergy's "largest petrochemical investment ever," said Saad Sherida Al-Kaabi, the Gulf state's energy minister and president of QatarEnergy.

The deal is also expected to help meet rising demand for polymers.

The facility will include an ethylene cracker unit with a capacity of 2.08 million tons per annum, and two high-density polyethylene units with a combined capacity of 2 million tons per annum, according to QatarEnergy.

The plant is expected to create more than 500 full-time jobs and around 4,500 construction jobs, the companies said.

The polyethylene produced by the project will mainly be sold to Asia, Europe and Latin America.

The material is used in producing durable goods like pipes for natural gas and water delivery, along with recreational products.