The company initially planned to spend $3.5bn on the project during this year, reported Reuters citing a source familiar with the matter.

In Iraq, international oil companies are paid a fixed fee for volumes produced in oilfields. However, falling oil prices and ongoing fight against Islamic State has forced the government to delay these payments.

The government has recommended oil companies to put new projects on hold and defer already finalized projects.

Located near Basra and around 20 miles from the Kuwaiti border, the Rumaila oil field covers 1,800km². It is expected to have stable production of around 1.4 million barrels per day this year.

In 2009, BP and CNPC consortium partnered with Iraq’s South Oil, to develop the oil field. BP owns 38% stake, while CNPC and State Oil Marketing Organisation (SOMO) have 37% and 25% respectively in the project.