"The biggest challenge is to have all these temporary facilities, which are subject to a lot of discussion in Brazil, in place," Valcke said in a FIFA video.
"Outside the stadium of Porto Alegre there is no pavement (paving) and we cannot put in place the television compound and all the different zones without any pavement."
"We are not talking about just the pavement you walk on. We are talking about 140,000 square metres and that takes at least two to three months and we are only three months away from the opening of the World Cup."
The World Cup kicks off in Sao Paulo on June 12.
Brazil's preparations have been plagued by delays and controversies and five of the 12 arenas missed the Dec. 31 completion deadline originally set by FIFA.
The Manaus stadium was officially opened on Sunday and the stadiums in Cuiaba, Sao Paulo and Curitiba are still not ready.
"It's not only FIFA that is in a race," said Valcke. "It's the local organising committee, the government and the cities who have to...have the stadiums, their facilities and the infrastructure in the cities ready to welcome the world."
Valcke said that once the stadiums had been completed, FIFA still had to make adjustments for World Cup matches.
"The good news would have been to have these stadiums by December 2013 and not March 2014 but the good news is still that we can work," he added.
- Sports & Recreation