By Brian Homewood

ZURICH (Reuters) - FIFA admitted on Friday that their largely Internet-based system of ticket sales for the 2010 World Cup may have been a mistake but added that stadiums will be at least 95 percent full for all matches after a sales surge.

Over-the-counter sales of tickets in host nation South Africa began last week, igniting real World Cup fever in the country for the first time and there was chaos as thousands of fans rushed to buy, crashing the computer system.

"I think we should have opened ticketing centers in the country before," FIFA general secretary Jerome Valcke told reporters on Friday.

"Yes, we have to think about our ticketing policies and maybe review the policy which limits people to buying four tickets for one game. We will learn for 2014.

The fifth and final stage of sales has seen 500,000 tickets put on offer and Valcke said that 200,000 had already been snapped up.

Until the last week's surge, there had been worries that swathes of empty seats could mar the tournament after tickets were returned from overseas and corporate customers.

"We're very confident of having a high number of people attending all 64 matches," Valcke said.

"The only World Cup with 100 percent occupancy was in 1994 in the United States but we will have at least 95 per cent occupancy of all stadiums."

However, Valcke said FIFA would not be cutting prices in a bid to fill seats.

"We are not giving any tickets away for free, there will be no discount on tickets," he said.

(Editing by Miles Evans)