Updated

Brazilian organizers have delivered another World Cup stadium. Yet there is little reason to celebrate amid doubts on when or even if the remaining five venues will be ready in time for football's showcase tournament in June.

The Arena das Dunas in the northeastern city of Natal was inaugurated in a Wednesday ceremony attended by FIFA Secretary General Jerome Valcke and Brazilian President Dilma Rousseff.

The event comes a day after organizers admitted there is a serious risk that the southern city of Curitiba may be dropped from the tournament because of a delay in stadium construction.

Brazil's World Cup organizing committee admits that FIFA may have to consider a Plan B for holding the tournament's matches, which would be an embarrassment for the country and football's governing body.