FIFA secretary general Jerome Valcke is giving Brazilian organisers only four weeks to show that the stadium in Curitiba will be ready in time for the World Cup.
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Valcke showed real concern about the pace of construction at the Arena da Baixada after visiting the southern city on Tuesday, saying that work there is badly late. The Frenchman remains hopeful the stadium will make it, but declined to guarantee it will be part of the tournament that begins in June.
Valcke said local organisers have until Feb. 18 to demonstrate that the work can be completed in time.
''What we are expecting is that these technicians will work from now up to Feb. 18 and by Feb. 18 they will say, 'OK, guys, it's fine,''' Valcke said.
Most of the delay at the venue, which is about 90 percent completed, was blamed on difficulties getting the needed funding for the construction. The stadium is being built mainly by local club Atletico Paranaense.
"For the time being, I trust that the decisions that have been made today will give us Curitiba as one of the host cities," Valcke told a news conference. "It will be a difficult birth, but at the end we will have a baby."
He added via FIFA's official website: "To be very honest, the situation as it stands is not ideal. The stadium is very delayed and well outside the delivery schedule to ensure best use by FIFA and the FIFA World Cup. But we have to be positive and that's why we have come together, as the main driving forces involved, to find solutions.
"By Feb. 18, the date of the Team Workshop in Florianopolis, where all 32 qualifying sides will be given important information about the FIFA World Cup, we have to decide between us -- the city of Curitiba, the state of Parana, Clube Atletico Paranaense football team, the LOC [local organising committee]and FIFA -- whether the stadium is in a position on that date to give us the confidence to hold World Cup matches there, without risking the organisation of the event.
"We will have people from FIFA and the LOC monitoring the stadium's progress on a daily basis and we will work together to guarantee that Curitiba will host FIFA World Cup games."
Now the ball is in the hands of Curitiba & the government to implement the measures pic.twitter.com/ggpDpZZl2h— Jérôme Valcke (@jeromevalcke) January 21, 2014
Brazil's deputy sports minister Luis Fernandes insisted that after Tuesday's visit it was clear something had to be done to guarantee Curitiba as a host city.
''With the current pace of construction, the stadium would not be ready in time,'' Fernandes said, adding that more workers are expected to be added to the construction site to try to get the venue ready.
The trip to Curitiba was not originally scheduled for this week's inspection tour by FIFA, but football's governing body added a stop there after receiving the latest construction report from local organisers. Valcke was initially expected to go to the Amazon city of Manaus.
Australia are scheduled to play defending champions Spain in Curitiba on June 23. On Wednesday, Football Federation Australia said it was concerned and will contact FIFA for more advice on the issue.
''The prospect of matches being moved from Curitiba raises serious concerns, particularly for Socceroos fans who have secured tickets and made flight and hotel bookings,'' an FFA spokesman said.
The Arena da Baixada was the most delayed among the six that still have to be delivered for the World Cup.
FIFA's inspection tour began on Monday in Sao Paulo, with Valcke visiting the Itaquerao stadium, where a crane collapse late last year killed two workers and caused significant delays in construction.
The Itaquerao, which will host the World Cup opener between Brazil and Croatia on June 12, is expected to be ready in mid-April.
On Wednesday, the Arena das Dunas in the north-eastern city of Natal will be the latest stadium to be passed ready and Valcke will be there for the inauguration ceremony along with Brazilian President Dilma Rousseff.
Brazil promised to deliver all 12 by the end of 2013 but only the six that were used during last year's Confederations Cup were ready. Four of those had missed their initial completion deadline of the end of 2012.
The Arena da Baixada is due to host four World Cup matches, all in the group stage. The first is Iran's clash with Nigeria on June. 16.