Reuters cited Saudi Aramco chief executive Khalid al-Falih as saying: "We expect start-up of some of the units, especially utilities, to take place in 2017, but the final completion would be in 2018 so that is the plan now.

"The foundation work is already ongoing by some of the construction contractors."

The Jizan refinery is being developed as part of the company’s $20bn investment plan, which includes development of 4,000MW power plant, a commercial port, and a refinery terminal in Jizan

Meanwhile, Saudi oil minister Ali al-Naimi said that the Jizan Economic City development project will not be affected by the plunging oil prices.

Naimi told reporters: "The development of Jizan… will continue, it will progress."