Argentina–Brazil relations

The Argentina–Brazil relationship is both close and historical, and encompasses the economy, trade, culture, education, and tourism. From war and rivalry to friendship and alliance, this complex relationship has spanned more than two centuries. The countries also share a system of government, a federal republic with a presidential system.

Rio de Janeiro was the first capital to recognize Argentine independence, whereas Buenos Aires’ was the first government to recognize Brazil's independence. After achieving independence from the Iberian crowns in the early nineteenth century, Argentina and Brazil inherited a series of unresolved territorial disputes from their colonial powers. The most serious breach in the relationship was the Cisplatine War (1825–1828), led by the Brazilian invasion and annexation of the Banda Oriental. Despite the numerous periods of muted hostility, the Argentine–Brazilian relationship was not defined by open hostility for most of the nineteenth and twentieth centuries. There was competition on many levels, and their respective defense policies reflected mutual suspicion, but the Brazilian economic rise in the 1980s led to the accommodation of Argentina as a secondary regional power and increasing cooperation.

With the creation of the Brazilian–Argentine Agency for Accounting and Control of Nuclear Materials in 1991, the two countries turned their nuclear competition into cooperation through mutual confidence. A high volume of trade and migration between Argentina and Brazil has generated closer ties, especially after the implementation of Mercosur in 1991.