6 Duty to declare national character of ship.U.K.
(1)An officer of customs and excise shall not grant a clearance or transire for any ship until the master of such ship has declared to that officer the name of the nation to which he claims that the ship belongs, and that officer shall thereupon enter that name on the clearance or transire.
(2)If a ship attempts to proceed to sea without such clearance or transire, the ship may be detained until the declaration is made.