Preferential Trade Agreements Harm Third Countries

We study market liberalisation under imperfect competition in the presence of price effects. For this purpose, we build a three‐country model of international trade under monopolistic competition. The neighbouring effect translates how the size effect propagates across countries. When a country increases in size, its relative wage increases, as well as that in a small and nearby country, whereas that in a large and distant country falls. We also show that a preferential trade agreement increases the relative wage, the welfare and the terms of trade in the partner countries, where the integration effect dominates, while lowering those in the third country.