Article 26 of the OECD Model Tax Convention on Income and on Capital and its Commentary

The competent authorities of the Contracting States shall exchange such information as is foreseeably relevant for carrying out the provisions of this Convention or to the administration or enforcement of the domestic laws concerning taxes of every kind and description imposed on behalf of the Contracting States, or of their political subdivisions or local authorities, insofar as the taxation thereunder is not contrary to the Convention. The exchange of information is not restricted by Articles 1 and 2.