The Transatlantic Trade and Investment Partnership (TTIP) is much more than another preferential trade agreement project: it aims to link the world’s two biggest economic entities. The initiative seems motivated by the stalemate in multilateral negotiations, the competition between trade agreements, and the willingness of the two partners to retain their leading positions in world trade, or at least to limit their loss of influence. Given the limited average level of the import tariffs – 2% in the US and 3% in the EU – these duties in most cases are not the most important stake (exceptions are a few sensitive products, mainly some dairy products, some clothing and footwear, and some steel items for the US, and meat products in the EU). Much more significant at the macroeconomic level are negotiations on non-tariff measures, regulation in services, public procurement, geographical indications, and investment, all of which are contentious. We first review the main issues at stake in each case and then use a computable general equilibrium model to assess the economic impacts of an agreement. Not all aspects of the negotiations can be incorporated in the model but it does account for the restrictive impact of non-tariff measures on trade in goods and of regulatory measures on trade in services. The corresponding levels of protection provided by the non-tariff measures are much higher on average than those provided by the tariffs, and they differ significantly across sectors, confirming their sensitivity in these negotiations. Our central scenario combines progressive but complete phasing-out of tariff protection accompanied by an across-the-board 25% cut in the trade restrictiveness of non-tariff measures, for both product and service sectors with the exception of public and audiovisual services. We find that trade between the two signing regions in goods and services would approximately increase 50% on average, including an upsurge of 150% for agricultural products. Eighty percent of the expected trade expansion would stem from lowered non-tariff measures. Both partners to the proposed agreement would reap non-negligible GDP gains, in the long run, corresponding to an annual increase in national income of $98bn for the EU and of $64bn for the US.

 Mots-clés : Trade Policy | International Trade Organizations | Computable General Equilibrium Models

 JEL : F13, C68