Milei, who attended a party meeting in São Paulo where Flávio Bolsonaro was named as the presidential candidate for his father Jair Bolsonaro's party on Saturday, called Lula da Silva a "thief" and "lawbreaker" in his speech.
The appearance of Milei as a guest in Brazil prompted the Foreign Ministry to first summon Argentina's ambassador and then resort to one of the sharpest diplomatic measures: recalling the country's ambassador.
Argentina's former president Alberto Fernández supported the criticism:
"Insulting the president of a sister nation and our largest trading partner is unforgivable."
