Rio organisers have yet to start construction on their second Olympic park in Deodoro while Nawal El Moutawakel, the IOC's head of the coordination commission said there were still outstanding issues related to government support.
"A number of unsolved issues remain with regard to the full alignment of government support," Moutawakel told the IOC session following a progress report by Rio Games chief Carlos Nuzman.
"Significant and tangible progress has been made. But constant supervision and assistance will be required over the coming months."
She said work on the Deodoro park was confirmed to start in May 2014, just over two years before the Olympics.
The IOC was highly critical of preparations as recently as September when Nuzman, himself an IOC member, was on the receiving end of tough questions from his Olympic colleagues over delays.
Organisers published the Games budget only a few months ago after being awarded the Games in 2009.
Rio organisers also have to deal with the fallout from protests over the use of funds for big events including this year's World Cup. More demonstrations have taken place since the start of the year.
"We have to make a great effort to communicate whenever possible, to enter in a dialogue," said IOC President Thomas Bach, who travelled to Rio in January to hold crisis talks with Brazilian president Dilma Rousseff.
"There is a good story to tell and Rio needs to tell it to the people to improve support," said the German.
"We showed our confidence during the visit but made it clear there is not a single day to lose," he said. "We are confident they can achieve this. Back to work there is no time to lose."
Image: Residents celebrate after Rio de Janeiro won the bid to host the 2016 Summer Olympic Games
Photograph: Sergio Moraes/Reuters
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