Professional boxers will compete at the Rio de Janeiro Olympic Games after the international boxing association AIBA approved a constitutional change on Wednesday, its president said.

AIBA boss Wu Ching-kuo said the change of the AIBA constitution was approved with 95 percent in favor - 84 of 88 voting members - paving the way for professionals to fight for medals for the first time at the Games starting on August 5.

Some 26 Olympic spots will be up for grabs when fighters compete at a qualifying tournament in Venezuela next month, with a total of 286 boxers - 236 men and 50 women - set to compete in Rio's boxing events.

AIBA spokesman Nicolas Jomard said there would be no wild cards, with the age limit at 40 for the athletes.

The move has drawn considerable criticism as many argue it would be unfair to amateur boxers who have trained for the Games for years and may now have to make way for the professionals.

Former world heavyweight champion Mike Tyson, who as an amateur won gold at the 1981 and 1982 Junior Olympic Games, has branded the move "ridiculous."

"It's ridiculous, it's foolish, and some of the pro fighters are going to get beat by the amateurs. It's just going to happen, I really believe that," the 49-year-old told Reuters last week.

He said the three rounds in the Olympic Games would work in favor of the amateurs, with professionals used to fighting as many as 12 rounds.

Northern Ireland's Carl Frampton, a former amateur who has won WBA and IBF world title belts at super-bantamweight, was also against allowing professionals into the Olympic Games.

"They're two different sports. It's like a badminton player playing tennis," he said on Twitter.

Jomard rejected claims of a disparity.

"There has been a lot of talk about disparity of level," Jomard said. "But it is not true."

He said professionals would just need to adapt to a different set of rules that was Olympic boxing.

"Olympic boxing has existed for decades and it is for them [professionals] to adapt and not the other way around. Why should we adapt for a minority?"

Under Wu's leadership, AIBA set up the semi-professional World Series Boxing (WSB) in 2011 in which fighters earned money competing for city-based teams. He also introduced women's boxing at the Olympic Games in London in 2012.

Amateur boxing has had its share of Olympic champions who have gone on to become top professionals, among them Muhammad Ali, Joe Frazier, George Foreman, Lennox Lewis, Oscar De La Hoya and Vladimir Klitschko.