China has been the key driver of global oil demand this year. Consumption, as defined by output plus imports, rose by 7.8% (900,000 b/d) to 12.42mn b/d for the first seven months of 2017, around half of total global growth for the same period.

Falling domestic output means the country’s crude imports have grown even faster – by a whopping 1.06mn b/d (14.2%) year-on-year to hit a record 8.53mn b/d for January-July. China’s voracious appetite for oil imports has made the...