China will revise its customs clearance procedures for crude imports as the world’s largest seaborne crude buyer faces severe port congestion.

Refiners in China rushed to purchase cheap overseas crude in the second quarter, resulting in long queues of tankers off Chinese ports that have struggled to handle record imports in recent months.

In a web statement, the General Administration of Customs said importing firms will be allowed to begin discharging crude once cargo samples are taken aboard from next month.