Sepp Blatter, the president of world football's governing body Fifa, has urged construction workers in South Africa not to wreck the 2010 World Cup.
Fifa president Sepp Blatter visits the stadium construction site in Durban
Blatter said the successful staging of the tournament lay in the hands of those preparing the event's ten stadia.
Blatter spoke to construction workers, who only recently ended a strike, as he visited Durban's Moses Madhida Stadium.
"I told them if they don't work, the realisation of the whole World Cup will be placed under threat," he said.
Construction was halted for nearly a fortnight earlier this month by a strike in Durban while workers have also downed tools in recent weeks at stadiums in Cape Town and the north eastern city of Nelspruit.
Unions had threatened to expand the strikes to cover all World Cup construction projects before a deal on pay and conditions was reached.
But Blatter has now revealed that workers in Durban will receive an end-of-year bonus if they did not strike again, and said he hoped the money-carrot approach will be adopted countrywide.
Blatter said that Durban was ahead of schedule but senior Fifa officials have acknowledged there are concerns that other stadiums, including in Cape Town and Port Elizabeth, are slipping.
Fifa secretary general Jerome Valcke said Port Elizabeth could lose the right to be one of the hosts of the 2009 Confederations Cup, the traditional warm-up for the World Cup, because of delays.
Blatter expressed concern last year that he had yet to see "picks and shovels" swinging into action.
Work is already behind schedule at Green Point in Cape Town
Asked if he was worried about the overall rate of progress recently, he replied: "No, no, no. I can say no because it's based on confidence."
Local Organising Committee (LOC) chairman Danny Jordaan, who accompanied Blatter on the Durban stadium tour, agreed the stadium issue was the most vital one facing the tournament.
"If we do not have the stadium then we do not have the World Cup," he told reporters.
Jordaan however said it was clear that progress was being made at every venue.
"In every single city we can now see the stadiums emerging out of the ground."