Deputy finance minister Vanessa Rubio said there must be an agreement between the government, the private sector and workers before the pension reform can move through congress.
Yamil Nazur was formerly risk director with the company's Chilean unit.
Mexico's central bank chief acknowledges the need for increased contributions to pension funds, but warned that raising mandatory rates could drive workers into the informal sector.
Mauricio Rodríguez Avellaneda has taken the helm of Previsora.
The Brazilian company seeks to acquire the equivalent of up to 280mn reais (US$123mn) in outstanding shares.