Galliot is one of an expected 300,000 gays, lesbians, bisexuals and activists expected to attend the eight-day World Pride 2000 festival this week, an event that has drawn the wrath of the Catholic Church as it marks its Holy Year.
"The ban did not come from the Pope personally," Gaillot told Corriere della Sera newspaper.
"The president of the French bishops' conference called me. He had been called by the Papal Nuncio in Paris who in turn had received the order from (Vatican Secretary of State) Cardinal Sodano who was speaking for the Pope," Gaillot said.
"The order had come down the whole chain of command as far as my mobile phone," he said.
Gaillot was forced out of his church office for recognizing homosexual unions and other violations of church policy.
Organizers of the gay pride festival, which started Saturday, promised civil disobedience if the Vatican and right-wing groups managed to block a permit for a march to the Colosseum planned to end the celebration.
"We're looking to achieve equality and respect," Deborah Oakley-Melvin, an organizer of the event and spokeswoman for the Mario Mieli gay support center in Rome, told Reuters, adding that the struggle for gay rights is something " the Church itself must acknowledge."
But the Catholic Church is reluctant to welcome into the fold an event which the faithful say dishonors the year-long celebrations of the 2000th anniversary of the birth of Christ, while championing a lifestyle the Church does not sanction.
The July 1-9 World Pride celebration coincides with several Holy Year events, including a special jubilee for Pope John Paul's Polish compatriots on July 2 expected to draw some 200,000 people.
"No one can expect the Church to define as good something which by the law of nature is evil," Secretary of State Cardinal Angelo Sodano, the most senior figure in the Vatican hierarchy after the Pope, said earlier this month.
The Rome city council, which first backed but then withdrew its support for World Pride, is deeply concerned about offending the Vatican during Holy Year and has not issued a permit allowing the parade route to take in the Colosseum.
Ironically, the first Holy Year in 1300, organized by Pope Boniface VIII, was held in part to divert attention from rumors of Papal sodomy.
The organizers say nothing will keep them from the Colosseum, and have vowed civil disobedience if necessary.
"If we don't get permission, we will form a peaceful human chain as far as the Colosseum on July 8," said organizer Titti De Simone.
The monument has been a powerful symbol of human rights this yeariis lit up whenever a death row prisoner is spared.
But right-wing groups are just as passionate about the planned march.
Mario Mieli offices have been spray-painted with a swastika and "no gay pride," said one organizer.
Demonstrations are planned by several far-right groups including Forza Nuova and the National Alliance party, which plans a torchlit parade from the Pope's cathedral to a Rome shrine.
"We wish to show solidarity with the Pontiff in the face of this attempt to muddy his name with such a provocative demonstration," the party said in a statement Thursday.