In addition, the economic convergence of countries creates favourable conditions for businesses of integrated countries, to certain extent protecting them from competition of companies from third countries; allows to its participants solve social problems in a single manner.
However, there may arise some contradictions and interests of the participants in groups.
Among the approaches to each stage of the integration only the customs union theory has received appropriate theoretical development.
This theory is narrowly focused only on the effect of reduction or elimination of duties in the merchandise trade, while the liberalization of nontariff barriers, trade in services and the movement of production factors are overlooked.
For example, the introduction of the EU single currency (euro) divided member countries into supporters and opponents.
The evaluation criterias of the integration grouping in terms of correspondence to the interests of the international economy in general are: the regional trade agreements should cover all sectors of the economy without exception; the transition period can not exceed 10 years and the liberalization of trade in selected industries must take place under a clear schedule; the trade liberalization on the most favoured nation treatment must precede or accompany the creation of any new integration grouping; the common customs tariff, introduced under the customs union can not be lower than the lowest tariff that existed in the country with the lowest tariff in the relevant field, or even the lowest tariff under the most favoured nation regime; rules for the admission of new members to the integration associations must be liberal and not prevent their expansion; rules of determining the country of origin must be transparent and must not be an instrument of protectionism within the grouping; rapid transition to the most advanced forms of integration that are more favourable, as they provide a more rational distribution and using of production factors; after the establishment of the integration antidumping regulations must not be applied among its members.
The integration of the developed countries is the necessity, defined by the achieved level of productive forces. The reasons of association of developing countries differ from the reasons according to which developed countries are included in this process. 508] and is a process of mutual accommodation and association of national economies of two or more states with uniform social systems.The evolution of integrative forms is investigated and the features of each stage are revealed. So, with these measures participating countries facilitate customs control in territory of each member.The role of the customs union as a prerequisite for the further development of integration in the long term is substantiated. In this case, the importance of customs controls increases at the external customs border of a single customs territory. economic integration customs union Results Integration processes have become crucial in world development for last decades, as well they influence on Ukraine's search of its place in the international labour division. Purpose of this article is to study the theoretical foundations of customs union creation as a form of the international integration.Depending on the form of integration the objectives of international economic integration are specified.While formation of free trade area and customs union (these forms of integration are the most common) participating countries tend to expand the market and provide the favourable environment for trade among themselves, as well as simultaneously prevent the competitors promotion of markets from the third countries.Development of economic integration undoubtedly has as its positive as negative effects on the parties.The formation of integration blocs considerably strengthens their economic potential, promotes commodity turnover, cooperation and industrial relations.