Rule 3 [ Service of interlocutory process out of Northern Ireland

Service of an interlocutory process out of Northern Ireland is permissible with the leave of the court on a person who is already a party to the proceedings and, in the case of a defendant, respondent or third party, has been served with the originating process but leave shall not be required for such service in any proceedings in which the originating process may by these Rules or under any enactment be served out of Northern Ireland without leave.]