Such adjustment is due if the adoption of the EU’s external tariff regime results in an increase in tariff beyond the level for which the acceding country has bound itself at the WTO, whilst taking ‘due account of reductions of duties on the same tariff line made by other constituents of the customs union upon its formation’.
Selline kohandamine on vajalik juhul, kui ELi välise tollitariifirežiimi vastuvõtmise tulemusena ületab tariif taseme, millega ühinev riik on ennast WTOs sidunud, võttes samal ajal „nõuetekohaselt arvesse tolliliidu teiste osaliste sama tariifirea tollimaksude vähendamist tolliliidu moodustamisel”.