Creation of ABACC

On 18 July 1991, Brazil and Argentina signed the Guadalajara Agreement, creating the Brazilian–Argentine Agency for Accounting and Control of Nuclear Materials (ABACC). This bilateral agency, unique in the world, was established to guarantee that all nuclear materials and facilities of both countries were used exclusively for peaceful purposes, ending decades of mistrust and competition.

For decades, relations between Brazil and Argentina were marked by a historic geopolitical rivalry and a security dilemma. In the 1970s and 1980s, both countries developed autonomous and secret nuclear projects, raising international fears of an arms race in South America.

Rapprochement began to gain traction after the end of the Itaipu dispute in 1979 and consolidated with the end of the military regimes and the presidential diplomacy between José Sarney and Raúl Alfonsín, who launched a gradual confidence-building process.

1. November 1990
   Signing of the Foz do Iguaçu Declaration, in which the two countries approve the Common System of Accounting and Control of Nuclear Materials (SCCC).
2. July 1991
   Signing of the Guadalajara Agreement (Bilateral Agreement), formally creating ABACC to manage and oversee the SCCC.
3. December 1991
   Signing of the Quadripartite Agreement between Brazil, Argentina, ABACC and the International Atomic Energy Agency (IAEA), establishing comprehensive safeguards and international inspections.

The creation of ABACC allowed Brazil to keep its nuclear program and its mastery of enrichment technology without suffering the international embargoes that isolated other countries. The mutual inspection model became a worldwide benchmark in diplomacy and disarmament, studied as an example of how neighbouring nations can resolve security dilemmas through institutional transparency.