However, this appears to exclude a large amount of the infrastructure costs.

"The budget for preparing the infrastructure of the World Cup is an absolutely open figure, it is 678bn rubles (AUD $13.2bn). These are total costs, including federal, regional and extra-budgetary source," said Sorokin.

"But I would not attribute this entirely to the costs for the World Cup. New terminals, new roads, metro stations have been built.

"The figure will be known up to a penny only after the World Cup, because even now there are some sudden expenses. But on the whole, we are within the limits of the World Cup organisation history, we will not surprise anyone with any high budget, under USD $500m (AUD $660m)," Sorokin said.

The total cost of the previous World Cup, in Brazil in 2014, was reported by Forbes to have been an astronomical AUD $20.5bn, while the 2010 edition in South Africa is said to have cost around AUD $5.2bn.

Sorokin said it was an "exaggeration" to claim that this year's World Cup was the most expensive in the history of the tournament.

He also noted that the number of unsold tickets for this summer's tournament was within normal parameters.

"You will find very few empty seats at stadiums during the group stage. Unsold tickets at each stadium are within tolerance - let's say, 1,000 to 1,500, no more," he said. "The rest of tickets, as you know, have recently gone on sale and were sold out instantly."