For the purpose of enforcing the provisions of any convention with respect to the conduct or safeguarding of fishing operations to which Her Majesty’s Government in the United Kingdom is a party a foreign sea-fishery officer may, in relation to a British fishing boat, and a British sea-fishery officer may, in relation to any foreign fishing boat, exercise anywhere within the convention area outside F1British fishery limits the powers conferred by section 8(2) and (3) above.

Nothing in this section shall authorise a British or foreign sea-fishery officer to do anything not authorised by the convention he is purporting to enforce or authorise him to exercise in relation to a boat belonging to a country which is a party to the convention any power which the government of that country has informed the other parties to the convention is not to be exercised in relation to its fishing boats.