Rousseff, who was removed from office in May pending an impeachment trial in the Senate, had been invited to attend the event in the Maracanã Stadium on August 5 by the interim Government led by her former vice-president Michel Temer.
Temer is now expected to officially declare the Games open, with the final result into the impeachment trial delayed until August 26 in order to avoid any potential fallout overshadowing the Olympics.
Concerns had been expressed about the diplomatic risks of having both Temer and Rousseff present alongside so many other international dignitaries.
“She is not going,” a Rousseff aide told Reuters today.
This follows the official insisting yesterday that she would not play “second fiddle” to Temer.