Christina Aguilera will not tour this summer as she previously planned. The pop star has instead opted to wait until sometime in 2011 to begin her North American concert schedule.

The 20-city summer tour was supposed to begin July 15 at Mohegan Sun Arena in Uncasville, CT. Tour promoter Live Nation attributed the year-long tour delay to Aguilera’s “prior commitments” for promoting her new album “Bionic” and upcoming film “Burlesque.”

“The singer felt she needed more time to rehearse the show and with less than a month between the album release and the tour date this wasn’t possible,” the statement explained.

Public ticket sales began just last week on May 21, and refunds will be available at the point of purchase. Aguilera’s new tour plans for 2011 will be announced later this year, according to Live Nation’s statement.

Aguilera’s summer itinerary was booked from its mid-July launch through an August 19 concert at Verizon Wireless Amphitheater in Irvine, CA. The singer’s fourth studio album “Bionic” is scheduled for release on June 8 in the United States.

Meanwhile, “Burlesque,” starring Aguilera as aspiring cabaret star Ali, has a planned Thanksgiving 2010 release date. The film, which reportedly finished shooting earlier this year, also stars Cher, Stanley Tucci and Alan Cumming, among other A-listers.

The 2010 trek would have been Aguilera’s first since her lengthy 2006-2007 Back to Basics Tour. Instead, it has become the latest Live Nation tour to be postponed this summer. Within the past week, Limp Bizkit cancelled its summer amphitheater concerts in favor of a fall arena tour, while U2’s tour was rescheduled to 2011 after Bono underwent emergency back surgery.

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