Brazilian President Dilma Rousseff called Hugo Chavez's death "an irreparable loss" on Tuesday and hailed him as a "great Latin American" and "a friend of the Brazilian people."
"We recognize a great leader, an irreparable loss and above all a friend of Brazil, a friend of the Brazilian people," she said before leading a minute of silence at a meeting with rural leaders in Brasilia.
Her predecessor, ex-President Luiz Inacio Lula da Silva, meanwhile expressed sadness over the death and recalled the Venezuelan leader's struggle for a "more just world."
Rousseff also canceled a trip that she was scheduled to make on Thursday to Argentina for talks with President Cristina Kirchner.
Chavez lost his battle with cancer earlier Tuesday, plunging his divided oil-rich nation into an uncertain future.
Venezuelan Vice President Nicolas Maduro, who struggled to hold back tears as he announced Chavez's death, said the government had deployed the military and police "to accompany and protect our people and guarantee the peace."