If:
(a) a native title application covers land or waters partly within the area for which a body is the representative body and partly within an adjoining area for which another body is the representative body; or
(b) a consultation, mediation, negotiation or proceeding relates to:
(i) a native title application; or
(ii) a future act; or
(iii) an indigenous land use agreement or other agreement in relation to native title; or
(iv) a right of access conferred under this Act or otherwise; or
(v) any other matter relating to native title or to the operation of this Act;
in respect of the areas referred to in paragraph (a);
the first - mentioned representative body may perform its facilitation and assistance functions, in relation to the application, consultation, mediation, negotiation or proceeding, for the part of the land or waters within the adjoining area, if it is acting in accordance with a written arrangement entered into with the other representative body.