The IRB has increased the number of core teams in the Sevens World Series from 12 to 15 from next season as the sport continues to build towards its Olympic Games re-inclusion in 2016.

The Hong Kong Sevens on 23-25 March, which is the only event on the calendar to feature 24 teams, will double as the qualification tournament.

Three teams will advance from a dedicated 12-team regional qualifier finale, securing coveted core team status and joining the current core teams - Argentina, Australia, England, Fiji, France, Kenya, New Zealand, Samoa, Scotland, South Africa, USA and Wales - in competing across all events in the 2012/13 Series.

The qualifying showpiece will run alongside another 12-team competition, also in the Hong Kong Stadium, contested by the current core teams.

The Hong Kong tournament will retain its status as the only 24-team event, and will continue to be played across three days on Friday, Saturday and Sunday, ensuring that fans continue to be treated to the high-quality, high octane entertainment that they are used to.

From the 2012/13 season onwards, promotion and relegation from core team status will come into effect with a 16th invitational team selected by the IRB for each event outside of Hong Kong.

IRB Chairman Bernard Lapasset said: "Sevens is going from strength to strength and we are seeing unprecedented interest in hosting, participation and sponsorship for the record-breaking Sevens World Series.

"As we build towards Rio 2016 and our Olympic Games debut it is important that opportunities exist for all nations to progress to Series core team status if they are good enough. The new system provides every nation competing in their regional qualifying tournaments with a direct opportunity to gain core team status and compete on every round of the World Series," he added.

In addition, and following the announcement that all participating teams will take points from every round of the 2011/12 Series, the IRB has confirmed that every round of the series will now carry the same number of points.

Formerly the Hong Kong tournament carried more points than the other rounds of the series. This will no longer be the case, bringing the series in line with other Grand Prix-style events such as Formula One.