Art. 6 para. 1 Dir 2009-72

Member States as well as the regulatory authorities shall cooperate with each other for the purpose of integrating their national markets at one or more regional levels, as a first step towards the creation of a fully liberalised internal market. In par­ticular, the regulatory authorities where Member States have so provided or Member States shall promote and facilitate the coop­ eration of transmission system operators at a regional level, including on cross-border issues, with the aim of creating a com­petitive internal market in electricity, foster the consistency of their legal, regulatory and technical framework and facilitate inte­gration of the isolated systems forming electricity islands that per­sist in the Community. The geographical areas covered by such regional cooperation shall include cooperation in geographical areas defined in accordance with Article 12(3) of Regulation (EC) No 714/2009. Such cooperation may cover other geographical areas.