The most favoured nation clause prevents one of the parties to the current agreement from continuing to remove barriers to another country. For example, in exchange for reciprocal concessions, Country A could agree to reduce tariffs on certain products from Country B. In the absence of a clause of the most favoured nation, Country A could still reduce tariffs on the same goods from Country C in exchange for other concessions. As a result, consumers in Country A could purchase the products in question at a cheaper price in Country C because of the tariff difference, while Country B would get nothing for its concessions. The status of the most favoured nation means that A is required to extend the lowest existing tariff to certain products to all its trading partners enjoying such status. If A later accepts a lower rate with C, B automatically gets the same lower rate. It should be noted that with regard to the qualification of the original criteria, there is a difference in treatment between inputs originating and outside a free trade agreement. Inputs originating from a foreign party are normally considered to originate from the other party when they are included in the manufacturing process of that other party. Sometimes the production costs generated by one party are also considered to be those of another party. Preferential rules of origin generally provide for such a difference in treatment in determining accumulation or accumulation. This clause also explains the impact of a free trade agreement on the creation and diversion of trade, since a party to a free trade agreement is encouraged to use inputs from another party to allow its products to originate.  In some circumstances, trade negotiations have been concluded with a trading partner, but have not yet been signed or ratified.
This means that, although the negotiations are over, no part of the agreement is yet in force. The creation of free trade zones is seen as an exception to the most privileged principle of the World Trade Organization (WTO), since the preferences of the parties to the exclusive granting of a free trade area go beyond their accession obligations.  Although GATT Article XXIV authorizes WTO members to establish free trade zones or to conclude interim agreements necessary for their establishment, there are several conditions relating to free trade zones or interim agreements leading to the creation of free trade zones.