（b）If agreement is not reached within sixty days after the notification provided for in subparagraph （a） above, the contracting party which proposes to modify or withdraw the concession may refer the matter to the CONTRACTING PARTIES which shall promptly examine it. If they find that the contracting party which proposes to modify or withdraw the concession has made every effort to reach an agreement and that the compensatory adjustment offered by it is adequate, that contracting party shall be free to modify or withdraw the concession if, at the same time, it gives effect to the compensatory adjustment. If the CONTRACTING PARTIES do not find that the compensation offered by a contracting party proposing to modify or withdraw the concession is adequate, but find that it has made every reasonable effort to offer adequate compensation, that contracting party shall be free to proceed with such modification or withdrawal. If such action is taken, any other contracting party referred to in subparagraph （a） above shall be free to modify or withdraw substantially equivalent concessions initially negotiated with the contracting party which has taken the action.