FIFA secretary general Jerome Valcke expressed his concern about preparations at three of the 12 World Cup stadiums during his final inspection of host cities.
During a two-week trip that ended Thursday, Valcke sent warnings to organizers in Natal, Porto Alegre and Sao Paulo, which will host the World Cup's opening match in two weeks.
He said it was a "race against the clock" in Natal and there was a lot "yet to be done" in Porto Alegre. In Sao Paulo, FIFA requested a second test event at the delayed Itaquerao Stadium that will host the Brazil-Croatia match on June 12. It is unlikely, however, that the venue will be tested at full capacity.
Local authorities are not expected to allow the sale of tickets at the test event for some of the temporary seating that was recently added to the venue, meaning the first time the 68,000-seat venue will be at capacity will likely be during the World Cup match.
Valcke said he was pleased with the work underway in the other nine host cities, including Curitiba, which earlier this year was nearly excluded from the tournament because of chronic delays.
Valcke's final stop on Thursday was in the northeastern city of Salvador, where he said there was "no time to waste" but praised the commitment of local organizers to make sure everything will be ready in time.
The game in Salvador on June 13 will be a much-anticipated rematch of the 2010 final, when Spain beat the Netherlands for the title in South Africa.
"All must be perfect that day," Valcke said on Twitter. "Pleased with Salvador's commitment to work with our on-site team to finalize remaining works for fans, media & teams."
Also Thursday, there was progress on plans for fan fests at Salvador and Recife. Salvador officials announced they reached a deal guaranteeing the organization of its fanfest, the FIFA-required event that allows fans to watch matches on large screens for free in public areas.
Organizers at Recife had been looking for private partners to promote a fanfest without having to spend public money, and Valcke said a solution had been found.
Valcke said he was pleased with the work at Recife's Arena Pernambuco, saying it was "on track for hosting" matches.
"Installations are taking shape really well here," he said.
The Arena Pernambuco was one the six stadiums built for last year's Confederations Cup, the World Cup warm-up tournament. FIFA wanted the other six venues completed by the end of 2013, but none met the deadline.
One of the stadiums that weren't ready in time was the Arena das Dunas in Natal, which Valcke visited on Wednesday.
In Sao Paulo, Valcke warned that it was "vital" another test event was scheduled to help ensure problems can be avoided during the high-profile opening match.