Dirty tanker rates leapt on the US Gulf to China route in July as state-run giant Sinopec switched from Russian to US crude, according to energy data analyst Vortexa.

All of the cargoes were earmarked for restocking Sinopec refineries outside Shandong province in expectation of an increase in demand for products in China.

China’s crude loadings from the US hit an 18-month high in July with an estimated 330,000 barrels per day (bpd) compared with just 60,000 bpd in the previous two months.