"American Idol" champion Kelly Clarkson canceled her Israel concert tour Thursday, saying a recently acquired throat illness has gotten worse.

Clarkson performed in Berlin Wednesday after canceling a Paris show, but her condition flared up afterward, and doctors advised her to refrain from singing until it healed, Ha'aretz news service reported Thursday.

Partner Telecom, owner of mobile phone operator Orange Israel and a major sponsor of the concert series, is expected to take a hit after investing approximately $400,000 in an advertising campaign and offering reduced price tickets to customers, Ha'aretz reported. The company said all tickets would be refunded.

Clarkson rose to fame after winning the first season of Fox TV's talent competition.