A/HRC/5/21 page 16 81. Members of the Advisory Committee are encouraged to communicate between sessions, individually or in teams. However, the Advisory Committee shall not establish subsidiary bodies unless the Council authorizes it to do so. 82. In the performance of its mandate, the Advisory Committee is urged to establish interaction with States, national human rights institutions, non-governmental organizations and other civil society entities in accordance with the modalities of the Council. 83. Member States and observers, including States that are not members of the Council, the specialized agencies, other intergovernmental organizations and national human rights institutions, as well as non-governmental organizations shall be entitled to participate in the work of the Advisory Committee based on arrangements, including Economic and Social Council resolution 1996/31 and practices observed by the Commission on Human Rights and the Council, while ensuring the most effective contribution of these entities. 84. The Council will decide at its sixth session (first session of its second cycle) on the most appropriate mechanisms to continue the work of the Working Groups on Indigenous Populations; Contemporary Forms of Slavery; Minorities; and the Social Forum. IV. COMPLAINT PROCEDURE A. Objective and scope 85. A complaint procedure is being established to address consistent patterns of gross and reliably attested violations of all human rights and all fundamental freedoms occurring in any part of the world and under any circumstances. 86. Economic and Social Council resolution 1503 (XLVIII) of 27 May 1970 as revised by resolution 2000/3 of 19 June 2000 served as a working basis and was improved where necessary, so as to ensure that the complaint procedure is impartial, objective, efficient, victims-oriented and conducted in a timely manner. The procedure will retain its confidential nature, with a view to enhancing cooperation with the State concerned. B. Admissibility criteria for communications 87. A communication related to a violation of human rights and fundamental freedoms, for the purpose of this procedure, shall be admissible, provided that: (a) It is not manifestly politically motivated and its object is consistent with the Charter of the United Nations, the Universal Declaration of Human Rights and other applicable instruments in the field of human rights law; (b) It gives a factual description of the alleged violations, including the rights which are alleged to be violated;