The removal of Assaf, who has survived numerous government reshuffles since taking the job in 1996, has been long expected amid a government shake up following the death of King Abdullah last year and sweeping economic reforms as the kingdom’s oil revenues falter.

According to a series of royal decrees issued yesterday, Assaf will be replaced by Mohammed al-Jadaan, chair of the country’s capital markets regulator.

Assaf, a close ally of the late king, was a key proponent of the lavish government spending that characterised the decade of substantial oil wealth in the kingdom before 2014.

But as prices collapsed over the past few years, Saudi Arabia has found itself in a dramatically different financial situation. Dependent on oil for 72% of its revenues, the government ran up a deficit of $98bn last year as prices plummeted.

The kingdom has moved swiftly to plug the budget gap and end its “addiction” to oil. King Salman has put his son, the deputy crown prince Mohammed bin Salman, in charge of economic reform plans.

The plan targets an $87bn worth of savings through a combination of spending cuts and growth in non-oil revenues. In September, the kingdom announced its first ever cuts to pay and perks for government employees in a bid to balance the books.

But public spending cuts have also hit the non-oil economy which the kingdom hopes to grow. The International Monetary Fund expects growth in this sector will slow to 0.3% this year.