Analysts note that Mercosur's economic momentum has slowed in recent years, particularly as trade disputes between Brazil and Argentina have flared. In a move aimed at protecting its trade surplus, Argentina has blocked and delayed imports from other Mercosur nations, and Brazil has retaliated by imposing barriers on imports from Argentina. Meanwhile, the Economist notes, although internal Mersocur trade has risen in absolute terms, it only represents a small percentage of members' total exports. The bloc "has not evolved into the seamless single market its founders dreamed of," the magazine says.