Rio de Janeiro, the capital of Brazil, is preparing to host a series of major, international sporting events leading up to the Olympics in 2016, including the Confederations Cup and the World Youth Day in 2013, as well as the FIFA World Cup in 2014.

The assurances followed complaints about expensive accommodation, heavy traffic and other infrastructure obstacles from delegates to the recent UN Conference on Sustainable Development in Rio.

The city's mayor, Eduardo Paes, said everything was on course for the project.

"The challenge to both cities (London and Rio) is enormous. Of course, Rio de Janeiro has a more ample handful of infrastructure interventions from a sports equipment point of view, perhaps many things already ready, but the city's infrastructure is surely more ample,” Paes said. “But I want to reaffirm that all the projects we agreed on with the International Olympic Committee have already begun."

Maria Silva Bastos Marques, president of Rio de Janeiro's Municipal Olympic Company, said Rio has the potential to double its current number of hotel rooms, certainly increasing it by at least 50 percent.

And the Brazilian organizers promised full venues for 2016, vowing to avoid the problem of empty seats that dogged the early days of the London Games, where organizers were confronted with television pictures showing swathes of empty seats.

The gaps have been blamed mostly on officials from sports governing bodies and national Olympic committees not using their allocations of prime seats but it angered many fans, desperate to get tickets but unable to.

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Source: AP

Editor: Huan CAO

Voiceover: Chris Clark

Producer: Flora Yue