Singer Rihanna has postponed Monday night's concert appearance in Houston.

The Rihanna Diamonds World Tour show was supposed to stop at the Toyota Center, but a statement from LiveNation confirmed the postponement.

“Unfortunately, as a result of illness Rihanna is unable to perform this evening at Houston’s Toyota Center,” according to a release.

Fans are instructed to retain their tickets to the event pending rescheduled show date information.

There is currently no change to the Dallas performance scheduled for Tuesday, April 16, at American Airlines Center.

For updated tour and ticket information, www.Rihannanow.com  or www.livenation.com.