Mercosur comprises Argentina, Brazil, Paraguay, and Uruguay.
Vieira, representing Mercosur's rotating presidency, described Viet Nam as an important trading partner for the South American bloc.
Argentina, Brazil, Paraguay, and Uruguay issued a joint statement with Viet Nam confirming the formal start of negotiations.
The parties are finalising terms of reference that will define the scope, structure, and methodology for talks, according to a statement posted on the Brazilian government's website. The agreement aims to boost trade and investment flows between South America and Southeast Asia.
The negotiations will focus on expanding trade through phased tariff reductions and elimination, whilst addressing related non-tariff measures to facilitate market access. Both sides said they want a framework consistent with World Trade Organisation rules and disciplines.
The terms of reference will identify negotiation areas whilst accounting for development levels and priorities on each side. The approach aims to ensure balanced negotiations that benefit both parties, the statement said.
Trade between Viet Nam and Mercosur totalled 11.46 billion USD in the first eleven months of 2025, roughly flat from the same period in 2024, according to Viet Nam's customs agency. Vietnamese exports to Mercosur rose by 15.9% to 3.59 billion USD. Imports from the bloc fell by 4.8% to 7.87 billion USD.
The agreement is expected to strengthen Vietnamese exports to Mercosur markets and boost competitiveness in the region. Both sides emphasised their commitment to diversifying trade and investment relations whilst deepening economic cooperation between the two regions.
The launch marks a significant step in South – South cooperation and opens the path for deeper economic integration, the parties said in their joint statement.
