customs clearance
US /ˈkʌstəmz ˌklɪr.əns/
UK /ˈkʌstəmz ˌklɪr.əns/

1.
the process of getting official permission for goods to enter or leave a country
:
•
The shipment was delayed due to issues with customs clearance.
•
You need to complete all the necessary documents for customs clearance.