Raggi had earlier been due to meet with Giovanni Malagò, president of Italy's Olympic Committee (Coni), but failed to turn up for the discussion, Italian media reported.
"I haven't seen Raggi. We waited, we waited but no-one turned up," Malagò told waiting media. "Now we're going, because a 35-minute wait is too much."
Their talk was going to be streamed live to the Italian public, for "maximum transparency" which Malago said had always characterized Coni's work.
The news of Raggi planned withdrawal of the bid had been widely expected, following months of criticisms from both the mayor herself and her party, Beppe Grillo's Five Star Movement. A city hall official confirmed Raggi's intention to reject the bid on Wednesday morning, Reuters reported.
The mayor, who took office in June, had been seen by most pundits as simply waiting for the end of the Paralympics in Rio to announce that City Hall will not be supporting the bid, which would scupper its chances of success. .
Raggi had continually repeated in her election campaign that the Games were not a priority for the Eternal City, a stance shared by the leader of the Five Star Movement, Beppe Grillo. Raggi made it clear she does not regard the Olympic bid a good idea for the cash-strapped city, but stopped short of saying she will not back it and had previously suggested holding a referendum to decide whether to host the games.
Prime Minister Renzi has deplored the party's stand, and dismissed their contention that the money use to host the Games could be better spent.
The president of the Fratelli d'Italia party, Giorgio Meloni, had started a Facebook campaign to convince Raggi to approve the Olympic bid, titled: Show Romans that you believe in this city.
Rome, which last hosted the Olympics in 1960, had been one of four candidates to host the Olympics in 2024 along with Paris, Budapest and Los Angeles. The quartet must submit the second part of their candidacy by October 7th.