Mexico City has dropped out of the race to host the 2009 International Olympic Committee Session and Olympic Congress.

The IOC's internal news Web site aroundtherings.com said Tuesday that Mexico City abruptly decided not to continue its bid, leaving Busan, Singapore, Copenhagen, Taipei, Cairo, Athens, Lausanne, Switzerland, and Riga, Latvia, as contenders.

Busan and Copenhagen are the frontrunners to host the two big events, which will elect the new IOC president and decide the venue for the 2016 Summer Olympics.

The host city will be selected in the IOC general meeting ahead of the Torino Winter Olympics opening February 8th.