When the General Agreement on Tariffs and Trade (GATT) came into force on January 1, 1948, preferential trade agreements were few and far between, the Benelux being probably the most important.
Today, some 350 preferential trade agreements are in place, all members of the World Trade Organization (WTO) are parties to at least one preferential trade agreement, there are preferential trade agreements where the parties are themselves other preferential trade agreements, and many WTO members participate in several preferential trade agreements at the same time: as of November 2021, the European Union participated in 45 preferential trade agreements notified to the WTO, Japan in 18, China in 16 and the United States in 14.
Preferential trade agreements are also seen as the most important source of trade policy reform in the last 20 years for most countries and increasingly associated with national security and foreign policy issues.
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