FIFA on Tuesday brushed aside lingering doubts about South Africa's readiness for the World Cup, as cities across the nation staged dance parties and celebrations to launch the 100-day countdown.

FIFA president Sepp Blatter insisted the country was ready to host Africa's first World Cup, which kicks off on June 11, and said he was bothered by naysayers who worry South Africa won't pull it off.

"It's not so much that there's pessimism but that it's always being thrown into doubt. It's bad, because when there's doubt, there's no confidence. For me and FIFA, that bothers us sometimes," Blatter told a news conference in Durban's new stadium.

"There is no doubt, no doubt," he said. "Let's go now, let's have this World Cup and then we will discuss at the end of July."

He spoke after a tour of South Africa's 10 stadiums that will host the month-long tournament. Construction is complete at all the stadiums and only two have yet to host games to try out the new facilities.

"We are on track, we are ready to make this World Cup and this is the main message following this inspection tour," FIFA secretary general Jerome Valcke said.

The 100-day countdown dominated South African media on Tuesday, with celebrations planned in all the country's main cities.