In announcing White's resignation last Friday night, Rumsfeld said a departure date had not been set.
Charles Krohn, the White House spokesman, said White and Rumsfeld had tentatively set June 11 for his departure, but Deputy Defense Secretary Paul Wolfowitz this week told White he should go May 9.
Rumsfeld has been traveling abroad since Saturday. In his announcement last Friday, Rumsfeld thanked White for his service but gave no clue why he forced him from the job. The two have been at odds over some aspects of the Army's modernization and weapons acquisition.
White, 59, has held the position since May 31, 2001. The Army secretary is the service's top civilian official. The top uniformed officer in the Army, the chief of staff, answers to the Army secretary.
White has not commented publicly on his firing by Rumsfeld. The White House has not announced who it intends to nominate to replace White. The nominee must be approved by the Senate.