He finds that at fixed tariffs, the only way to integrate between two
regional blocs is through FDI, which leads to full trade diversion and investment creation.
The effect of FDI on the tariff level is also analysed. Given that high tariffs would
encourage FDI more than they encourage exports, MNCs exert a pressure upon the bloc's
capacity to set high tariffs and prevent tariff wars internationally. Nevertheless, it looks to
us that if the purpose of the bloc is to protect itself from both FDI and exports from nonmembers
(for which a justification has also to be found), then setting lower tariffs may
indeed increase the opportunity-cost of MNCs to invest in the bloc, but it also reduces the
cost of exports! Moreover, as highlighted by Motta and Norman (1996), regional blocs will
benefit more in terms of welfare if they concentrate on reducing internal barriers rather
than coordinate on tougher external trade policy. The explanation is that since FDI is
beneficial for the host country, each member of the RIA has an incentive in encouraging it,
but non-bloc MNCs will flow in only under the condition of ‘market-accessibility’, which is
ensured by minimising the level of intra-bloc trade barriers. Finally, whatever is the
assumed relationship between exports and FDI (complements or substitutes) or the nature
of FDI (horizontal or vertical) a tariff reduction will always benefit imports of intermediary
goods in the host country or imports of the final good in the home country, hence
favouring both exports and FDI.