Brent crude broke the $48 per barrel mark this afternoon taking it to its lowest level since April 2009.
Earlier today Goldman Sachs slashed 2015 forecasts for Brent crude to $50 per barrel (down from $83) and $70 per barrel in 2016 (down from $90).
It said "to keep all capital sidelined and curtail investment in shale until the market has re-balanced, we believe prices need to stay lower for longer".
US crude also suffered, shedding $1.22 to $47.14 per barrel which was even further below the £50 per barrel mark.
Since mid-2014 oil prices have crumbled amid a glut in the global supply of oil, the burgeoning US shale gas industry and depressed demand from countries such as China.
Falling oil prices have hurt oil companies and the world's oil producers such as Russia and Saudi Arabia. But consumers have cheered cheaper petrol prices while airliners like Ryanair and British Airways have been gifted with cheaper fuel.