Square Enix Co. Ltd. and Disney Interactive Studios announced today (via PR Newswire) that the latest game in their Kingdom Hearts series will arrive in North America exclusively on the Sony PlayStation Portable system on September 7th, 2010.

Entitled Kingdom Hearts: Birth by Sleep, this prequel to the role-playing game series which melds Disney characters with those from Square Enix’s Final Fantasy series will feature roles played by veteran voice actors such as Mark Hamill, James Woods and Leonard Nimoy. The game will also be the first official appearance for Bret Iwan as the fourth voice of “King” Mickey Mouse-his predecessor, the late Wayne Allwine, passed away last year after the completion of his work on the previous Kingdom Hearts game, Kingdom Hearts 358/2 Days.

In addition to the game itself, Square Enix and Sony Computer Entertainment America will release an “Entertainment Pack,” which will release simultaneously with the game by itself and will include:

• a “Mystic Silver” PSP-3000 system
• the Kingdom Hearts: Birth by Sleep game
• a (yet-to-be-determined) movie whose content is unrelated to the Kingdom Hearts series
• and a 4GB Memory Stick PRO Duo for data storage.

Kingdom Hearts: Birth by Sleep has been rated “E10+” by the Entertainment Software Ratings Board for “fantasy violence and mild, suggestive themes.”