For years, the Opec oil cartel was able to watch the meteoric rise in oil prices with delight. But as benchmark futures broke through $100 a barrel and began to approach this summer’s eventual peak of $147, an uneasy sense of foreboding set in. Opec ministers worried the high cost of petrol, especially in the US, would begin to erode demand.

In June, the political pressure peaked. Washington became agitated, London cried foul and governments across Asia struggled to maintain their ever more expensive fuel subsidies.