The big winners of high oil prices are not the international oil companies being criticised by politicians for their enormous profits, but rather the oil services companies that the majors rely on for equipment and labour.

Wood Mackenzie, the energy consultants, say that over the past three years, large oil service company revenues have on average tripled, with net margins rising even higher, outperforming the far better known majors, ranging from ExxonMobil to BP.