Article 6 — Cooperation between national supervisory authorities

1. The national supervisory authorities shall exchange, in the framework of the National Supervisory Authorities Cooperation Board referred to in Article 18, information relevant for other national supervisory authorities, in particular information relating to their work and decision-making process, best practices and procedures in the application of this Regulation. 2. The national supervisory authorities shall cooperate, where appropriate, through working arrangements, for the purposes of mutual assistance in their tasks laid down in Article 5 and the handling of investigations and surveys. 3. In the case of cross-border provision of air navigation services in airspaces falling under the responsibility of two or more Member States, the Member States concerned shall ensure that the necessary agreements for the supervision of those services are concluded. The national supervisory authorities concerned shall facilitate the provision of those cross-border services by air navigation service providers and may establish appropriate working arrangements or oversight plans specifying the implementation of their cooperation. 4. In the case of cross-border provision of air navigation services in an airspace falling under the responsibility of another Member State, the agreements referred to in paragraph 3 shall provide for the mutual recognition of the discharge, by each of the Member States or their authorities, of the tasks set out in this Regulation and of the results of the discharge of these tasks. They shall also specify which national supervisory authority shall be in charge of the tasks set out in Article 5(1). 5. Where permitted by national law and with a view to regional cooperation, national supervisory authorities may also conclude agreements on the division of responsibilities regarding the supervisory tasks. 6. Agreements referred to in this Article shall be notified by the Member States concerned to the Commission.