KEY POINTS

Oil fell to its lowest levels in a year and a half on Thursday as a glut in supply and weak demand weighed on prices. But while Brent crude recovered some of those losses on Friday, the outlook for oil remains weak and sanctions imposed on Iran are likely to make matters worse, Dan Yergin, co-founder and chairman of energy research consultancy Cambridge Energy Research Associates (IHS CERA) told CNBC.

Speaking to CNBC from St Petersburg’s International Economic Forum, Yergin said that crude oil prices had dropped sharplybecause of a large build-up of supply and a lack of demand for the commodity, despite the oil security threat from Iran.