Which South American nation saw its newly elected president take office in December 2025, promising economic reforms?

The South American nation that saw its president promising economic reforms in December 2025 was Argentina. While Javier Milei actually took office as Argentina's president on December 10, 2023, following his victory in the 2023 general election, his ambitious economic reform agenda was a dominant topic and continued to unfold throughout 2025.

Milei, a self-described anarcho-capitalist, campaigned on a platform to radically transform Argentina's struggling economy. His promises included tackling chronic inflation, reducing the fiscal deficit through significant spending cuts, and implementing broad deregulation. Upon taking office, his administration immediately began enacting these "shock therapy" measures, which involved a substantial devaluation of the peso and efforts to control the money supply.

By December 2025, these reforms had been ongoing for two years, with significant developments, including a decisive victory for his party, La Libertad Avanza, in midterm legislative elections in October 2025. This electoral success strengthened his political hand, making it easier to push through his program of radical spending cuts and free-market policies aimed at stabilizing the economy and fostering growth. The ongoing nature and impact of these reforms made Argentina a focal point in current events related to economic transformation in South America.