Over half of the total tickets for this year's Rugby World Cup in Japan have been sold, an official source said Monday.

Over 1 million of a total 1.8 million tickets available for the 48 games over 12 venues have been sold. The local organizing committee is aiming to sell out every match, with the remaining tickets to be put on sale this month.

Sales began in January 2018 with priority group lotteries which resulted in over 600,000 tickets sold. General ticket sales began in September.

With these sales together with tickets distributed through World Rugby now exceeding 1 million, organizers appear on track to secure the projected total ticket revenue of 26 billion yen ($236.4 million).

According to an official with the local organizing committee, one reason for the strong sales is Japan's performance at Rugby World Cup 2015, which included a win over South Africa -- arguably the sport's greatest upset.

Tickets for Japan's pool stage games and for the final have been dubbed "platinum tickets" by organizers as they are the hardest to obtain.

The next round of ticket sales will begin on Jan. 19 and last until March, when all remaining tickets -- including the few left for Japan's games -- will be available on a first-come, first-served basis.

Tickets unclaimed by World Rugby stakeholders will be available for sale after May, as will tickets returned by the original purchasers.