Oil prices have risen in recent weeks to their highest levels since 2014. Falling oil production in Libya and Venezuela have driven the surge, along with a drop in Iranian crude exports due to US sanctions. That's good news for oil exporters, but it's caused anger in countries that buy oil, where people are feeling the pinch at the petrol pumps. Laila Humairah has more. We speak to David Elmes, professor at Warwick Business School.