flag of convenience
noun [ C ]
ukusplural flags of convenience COMMERCE, TRANSPORT
the flag of a country that will register a ship (= list it as a ship of that country) that is owned by someone from another country:
Even some landlocked countries offer flags of convenience in order to gain income.
An increasing part of the world's merchant fleet is operating under a flag of convenience, chiefly for financial reasons involving lower taxes and less stringent regulations.