Shell boss Voser warns Europe must 'stay competitive'
6 June 2013 Last updated at 13:03 BST
The head of oil giant Shell has told the BBC that Europe faces a growing struggle to compete with the US economy.
Cheap energy released by the process of fracking has revolutionised the US energy market.
Gas and oil discoveries in shale rock have led to a boom in gas and oil production in recent years dramatically reducing gas prices.
Royal Dutch Shell's chief executive Peter Voser told the BBC's John Moylan that the challenge in Europe was "to stay competitive".