OPEC has aimed to drain OECD inventories below the five-year average, an objective that looks to have been completed recently. However, now they have their sights on China’s oil inventories, which have been on the rise.

The problem is that precise data on Chinese inventories is hard to come by, but Ursa Space Systems, an oil data company, estimates that inventories have climbed by 130 million barrels over the past year in China.

OPEC is concerned about boosting oil production while China is sitting on a mountain of supply.