"There will not be any empty seats in the stadiums. That was a commitment we made from day one," FIFA general secretary Jerome Valcke told Reuters. "I am now much more optimistic than three weeks ago."
World football's ruling body has admitted its largely internet-based system of ticket sales for the tournament starting on June 11 may have proved less than efficient.
"People are waking up very late but we are very happy with the result and all of the people involved are very confident," Valcke said, speaking on the sidelines of an international sports conference in the United Arab Emirates.
"With about 45 days before the World Cup, we have more or less 40 matches sold out already, up from 29 only a short time ago," he said.
FIFA initially made tickets available only on the internet and was criticised for misunderstanding South African culture where the poor black fans who are soccer's biggest supporters do not have access to computers or bank accounts.
