Ariana Grande will not perform at Tampa's Amalie Arena tonight due to an unspecified illness. The announcement came via a news release from Live Nation hours before doors were set to open at the sold-out concert.

Grande's Wednesday night show at the Amway Center in Orlando has also been postponed, the release said. The concerts, part of the pop star's Sweetener World Tour, have been rescheduled for Nov. 24 in Tampa and Nov. 25 in Orlando.

"Ariana is sorry to disappoint her fans and will look forward to seeing them in November," the release said.

On Instagram, the star wrote that she was "so beyond devastated."

"I woke up incredibly sick today, ran to my doctor here and have been told to postpone these shows tonight and tomorrow," Grande posted Tuesday. ... "I will make this up to you, I promise. Pleas forgive me. I love you and I will be back and better than ever as soon as possible."

Tickets to the Tampa and Orlando concerts are still good for the new dates. Refunds are also available at "point of purchase," the release said.

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Contact Christopher Spata at cspata@tampabay.com.