On Tuesday, the All-Russian Association of Passengers filed a complaint with the Russian Federal Antimonopoly Service, claiming that average ticket prices for flights between Moscow and other host cities during the World Cup had doubled, and asked the service to look into the matter.

"As of today no collective dominance of the airlines on any of the routes has been found. Ticket prices are being formed in a competitive environment," the statement published on the FAS official website read.

FAS also said that there was an increased demand for tickets for the days of the tournament and that almost no economy class tickets were left.

Russia will host its first-ever FIFA World Cup between June 14 and July 15, with matches set to take place in 11 host cities, including Moscow, St. Petersburg and Sochi.