Investors are uncertain how Fernandez will handle the country`s economic challenges. Fernandez, who will succeed market-friendly President Mauricio Macri has not detailed yet the party's plans for Latin America’s No. 3 economy.

Sergio Rial, who is also chief executive of Banco Santander Brasil SA, was named head for South America in April as Santander seeks to ramp up growth in its key emerging market region. He oversees the Andean region, Argentina, Uruguay and Chile.

Rial said in April that the bank would re-launch its consumer unit in Argentina, saying it might offer the highest upside for the bank in South America.

Argentina in the first nine months of 2019 accounted for only 1% of the Spanish group's total profit.

Earlier on Wednesday, Banco Santander CEO Jose Antonio Alvarez said the bank sees solid growth in South America despite uncertainty in Argentina after Fernandez's victory over Macri.

(Reporting by Carolina Mandl; and Leslie Adler)

By Carolina Mandl