Article 53: United Nations Charter

(1) The Security Council shall, where appropriate, utilize such regional arrangements or agencies for enforcement action under its authority. But no enforcement action shall be taken under regional arrangements or by regional agencies without the authorization of the Security Council, with the exception of measures against any enemy state, as defined in paragraph 2 of this Article, provided for pursuant to Article 107 or in regional arrangements directed against renewal of aggressive policy on the part of any such state, until such time as the Organization may, on request of the Governments concerned, be charged with the responsibility for preventing further aggression by such a state.(2) The term enemy state as used in paragraph 1 of this Article applies to any state which during the Second World War has been an enemy of any signatory of the present Charter....Article 53 governs and limits the permissibility of enforcement measures by regional arrangements or organizations (Art. 52). The Article mentions two distinct possibilities. The SC may decide on the necessity of enforcement measures and utilize regional arrangements to carry them out or regional arrangements may decide on the necessity of enforcement measures and seek the SC's authorization in order to be able to carry them out legally. To utilize regional arrangements or regional agencies means to utilize the States parties to a regional arrangement and hence members of a regional organization either directly, or indirectly by utilizing the agency constituted by a regional arrangement. Under Art. 53(1) c1.1, the regional organization functions as a subsidiary organ of the UN. 4 In either case, the SC retains the responsibility both for the execution of the enforcement action through the regional arrangement (cl. 1) or for the authorization of enforcement measures taken by regional arrangements (cl. 2).