IOC members grilled the head of the 2016 Rio de Janeiro Olympics on Sunday about delayed preparations for South America's first Games.

Carlos Nuzman, head of the Brazilian Olympic Committee and the Rio Games, offered few concrete responses to blunt questions on Sunday as he sat in front of about 100 IOC members during their general assembly in Buenos Aires

A team of IOC inspectors, headed by Morrocan Nawal El Moutawakel, visited Rio a week ago and warned that work must be sped up. El Moutawakel sat near Nuzman and repeated the need for transparency in preparations and better cooperation between various levels of government.

She urged more cooperation to address what she termed "challenging aspects of the Olympic project".'

In prepared remarks before taking questions, Nuzman attempted to allay concerns among his IOC colleagues.

"We have made significant progress,"' he said. "I can assure you once again: Rio will be ready. There is a lot of work ahead. We fully understand our task."

Not everyone was convinced.

Kevan Gosper of Australia, head of the IOC press commission, had questions about media preparations, and then offered frank advice.

"You simply have to keep your public informed (about) what's happening," Gosper said. "The biggest commitment you have is to explain the principles of social investment impacting on your city as you're preparing for these Games. If the community doesn't get it, you will have a repeat of what you had."