Christina Aguilera called in to MTV's "TRL" Thursday (April 29) to announce she's calling off her upcoming tour with Chingy. The singer has vocal strain and has been advised to give her voice some immediate rest.

Doctors told Aguilera that she shouldn't sing for the next six weeks -- bad news for anyone expecting to see her or Chingy on the 29-date outing that the two had planned (see [article id="1485609"]"Christina Aguilera/ Chingy Tour Takes Shape"[/article]). The second leg of her Stripped tour was to kick off May 13 in Auburn, Washington.

"I'm extremely disappointed to have to cancel this tour," Aguilera said in a separate statement. "I was looking forward to being on the road again and spending time with my fans."

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