Madonna has postponed her career-spanning Celebration tour due to what her manager called a "serious bacterial infection" and her ongoing recovery.

Manager Guy Oseary wrote on Instagram Wednesday that the singer had spent several days in an intensive care unit after becoming ill on Saturday. He said the 64-year-old singer is expected to make a full recovery.

The tour was set to kick-off in Vancouver on July 15.

"Her health is improving, however she is still under medical care," Oseary wrote.

Live Nation confirmed the tour postponement, citing Oseary's post.

The Celebration tour is scheduled to make stops in Detroit, Chicago, New York, Miami, Los Angeles, Denver, Atlanta and Boston, among other cities and its first leg was slated to end on Oct. 7 in Las Vegas. Oseary said details about rescheduled dates would be shared soon.