The last decade has witnessed widespread and rapid formation of regional trading agreements simultaneously to the growing of the trade liberalisation and the establishment of the World trade organization. This rapid spread of RTAs is surely the most important recent development in the world trading system. This is now an important challenge to the world trading system, particularly when RTAs continue to proliferate as progress on the Doha round has slowed.
It is not clear why states constitute preferential economic blocs when they belong to a multilateral system in which the norm of nondiscrimination in trade is the cornerstone, while RTAs violate obviously this norm.
This paper will first outline briefly the history and the economic theory of RTAs and treatment of RTAs in the WTO/GATT. It will then discuss the question of compatibility between WTO rules and the exigencies of RTAs.
Key words: Economic blocks, international trade, most-favored-nation (MFN), multilateralism, regionalism, regional trade agreements (RTAs), world trade system.