Traffic in front of the iconic building was temporarily interrupted and onlookers cheered as Robert reached the top of the building, where police awaited him, Costa said.
Robert, known for scaling some of the world's tallest and best known buildings without ropes or other equipment, tried to climb the Edificio Italia on Sunday, but police detained him before he was able to begin.
He returned to the building every day since, but administrators hired security guards to follow his steps inside the building, thwarting other attempts.
While Robert was not authorized to climb the building, which contains offices for more than 130 companies, he was allowed to roam freely inside its public areas.
On Wednesday afternoon, he took an elevator to the roof and "took advantage of a small lapse in security" to make his way outside, Costa said.
The 45-year-old has climbed more than 70 skyscrapers around the world, including the Eiffel Tower, the Empire State Building, the Sears Tower and the Petronas Towers in Kuala Lumpur, according to his Web site.
