There are economic as well as political reasons why nations pursue economic integration. The economic rationale for the increase of trade between member states of economic unions rests on the supposed productivity gains from integration. This is one of the reasons for the development of economic integration on a global scale, a phenomenon now realized in continental economic blocs such as ASEAN, NAFTA, SACN, the European Union, AfCFTA and the Eurasian Economic Community; and proposed for intercontinental economic blocks, such as the Comprehensive Economic Partnership for East Asia and the Transatlantic Free Trade Area.