5 Parties to the conflict may agree on the creation of unre-defended places, even if they do not meet the conditions set out in paragraph 2. The agreement should define and describe as precisely as possible the boundaries of the unre defended place; If so, it can define monitoring methods. Neutral observers may be placed on board these vessels to check the equipment carried out by the parties to the conflict. To this end, free access to the devices is granted. Once the parties concerned have agreed on the geographical location, management, food supply and monitoring of the proposed neutralized area, a written agreement is reached and signed by representatives of the parties to the conflict. The agreement defines the start and duration of the neutralization of the area. Parties to the conflict may, either unilaterally or through certain agreements, bring neutral observers on board their ships who verify strict compliance with the provisions of this convention. The conditions for sending individual parcels and collective discharge are subject, if necessary, to special agreements between the powers concerned, which should in no way delay the receipt of aid by prisoners. Books should not be included in packages of clothing and food. Medical assistance should normally be sent in bundled packages. All remittances sent by mail, including remittances sent by parcels and sent by other countries to internees or sent by mail, either directly or through article 136 information offices and the Central Information Agency in accordance with Article 140, are exempt from any postal costs, both in countries of origin and destination and in intermediary countries.

To this end, in particular, the exemption granted by the 1947 General Postal Convention and the Conventions of the General Postal Union in favour of civilians of enemy nationality held in camps or civilian prisons are extended to other internees protected by this Convention. Countries that have not signed these agreements are required to grant conditions at no cost under the same circumstances. 7 A place loses its status as an unreclused place if it no longer complies with the provisions of paragraph 2 or the agreement covered in paragraph 5. In this case, the place continues to enjoy the protection provided by the other provisions of this protocol and by the other rules of international law applicable in armed conflicts. If no agreement has been reached on the investigation procedure, the parties should agree on the choice of an arbitrator to decide on the procedure to be followed. In and beyond land areas physically controlled by friendly forces or maritime areas that are not physically controlled by an unfavourable party, the respect and protection of medical aircraft of a party to the conflict does not depend on an agreement with an opposing contracting party. However, in order to enhance safety, a party to the conflict operating its medical aircraft in these areas may notify the adverse party in accordance with Article 29, particularly if these aircraft operate flights that place them within range of the relevant contracting party`s surface-to-air weapons systems.