Organisers of the Soccerex Global Convention have confirmed the upcoming event in Rio de Janeiro has been cancelled due to civil unrest.
The decision, made by the Rio de Janeiro State Secretary of Sport, was revealed by Soccerex on Tuesday and is likely to raise more questions over safety ahead of next year's World Cup in Brazil.
Soccerex have notified the Rio State Government of their intention to initiate legal proceedings in order to seek compensation.
A Soccerex statement said: "Preparations for the event at the Maracana Stadium were well advanced with content planned, speakers confirmed and partnerships in place.
"To be summarily cancelled in such a cavalier fashion, having hosted 33 events over five continents is extremely frustrating but nevertheless it has happened and is in contravention of all of the contractual obligations of the Rio State Government, who have been notified of our intention to instigate legal proceedings for substantial compensation."
Protests were held during this year's Confederations Cup in Brazil, mainly over the cost of hosting the World Cup when some Brazilians feel the money should be spent on health, education and transport.
Soccerex chief executive Duncan Revie said: "On behalf of all at Soccerex, I would like to apologize to every business, football club, league, federation and media organisation affected by this news.
"This unique and cruel conclusion to our time in Rio was completely out of our hands and everyone who has attended a Soccerex event over the last 18 years will know this is not how we do business.
"We must look forward now to 2014, to our new event calendar and the Global Convention in Manchester."
The annual conference, which brings together key figures in the game from across the globe, was due to be held at the iconic Maracana Stadium - the venue for the 2014 World Cup final - from November 30 to December 5.