4. Where an offence is alleged to have been committed on board any ship belonging to the Socialist Federal Republic of Yugoslavia by the master or a member of the crew, proceedings for the offence instituted otherwise than at the request or with the consent of a consular officer of the Socialist Federal Republic of Yugoslavia shall not be entertained by any court in the United Kingdom, unless—
(a)the offence is alleged to have been committed—
(i)by or against a person who is a citizen of the United Kingdom and Colonies, a citizen of Southern Rhodesia, a British subject by virtue of section 2, 13 or 16 of the British Nationality Act 1948 or the British Nationality Act 1965, or a British protected person within the meaning of the said Act of 1948; or
(ii)against a person other than the master or a member of the crew; or
(b)the offence is one involving the tranquillity or safety of a port, or the law relating to safety of life at sea, public health, oil pollution, wireless telegraphy, immigration or customs; or
(c)the offence is one punishable (on a first conviction) with imprisonment for a term that may extend to five years or with a more severe sentence.