Meanwhile, Australia, Ireland, Italy, Japan, Russia, Scotland, South Africa and Wales have formally confirmed their commitment to host the 2019 tournament. The deadline to confirm intention to tender was September 30.
Each Union had six weeks to review in detail the Rugby World Cup tender document before formally expressing their intention to tender.
Only Jamaica has opted not to continue with a bid to host a RWC tournament.
IRB Chairman Bernard Lapasset said: "This strong response is unprecedented and truly reflects the global attraction of the Rugby World Cup tournament.
"It also reflects the significant economic benefits that accompany the hosting of a tournament that has grown in stature and prominence as a global event. The Rugby World Cup is now firmly established as one of the world's top five sporting events.
"It also ensures that future development investment initiatives in the game worldwide can continue to be underwritten by the tournament and planned accordingly.
"The IRB Council will announce the RWC 2015 and 2019 host Unions in July 2009, six years prior to the first tournament and 10 years prior to the 2019 event.
"This timetable reflects the scale and nature of the preparatory work in delivering this world class tournament," he added.
The 10 Unions now have until May 8, 2009 to submit their detailed tender responses to RWCL.
The responses will then be reviewed by RWCL before the tender Unions will be invited to make a presentation to the IRB Council in May 2009.
The host Unions for Rugby World Cup 2015 and Rugby World Cup 2019 will be selected at a special meeting of the IRB Council on July 28, 2009.