Whistleblowers claimed the IEA figures were unreliable and subject to political manipulation – something the agency categorically denies. But the subject of oil reserves touches not just energy and climate change policy but the wider economic scene, because hydrocarbons still oil the wheels of international trade. Even the Paris-based IEA admits that the world still needs to find the equivalent of four new Saudi Arabias to feed increasing demand at a time when the depletion rate in old fields of the North Sea and other major producing areas is running at 7% year on year.