Saudi Arabia is burning through its foreign reserves at a record rate, as the kingdom seek to maintain spending plans despite lower oil prices. The central bank’s foreign reserves have dropped by $36bn, or 5 per cent, over the past two months, as newly crowned King Salman bin Abdulaziz Al Saud dips into Riyadh’s rainy-day fund and increases domestic borrowing to fund public-sector salaries and large development projects.