International Finance Discussion Papers: Multilateralism and the Endogenous Formation of PTAs

This paper examines the interaction between preferential trade agreements (PTAs) and multilateral tariff reduction in a model of imperfect competition. A growing literature finds that the formation of PTAs alters the incentives for and the sustainability of multilateral tariff reduction. We show that the causation is not one-sided -- multilateral tariff reduction also affects the formation of PTAs. Specifically, tariff reduction enhances the incentives to form a PTA and increases the likelihood that it is self-enforcing. Thus, each round of multilateral tariff reduction should lead to a new wave of PTAs. This may help to explain the current trend towards regionalism.