Keith Urban [ tickets ] is suffering from "a sudden vocal chord ailment" that has forced him to cancel some upcoming concert and promotional appearances, according to his official website.

A doctor has recommended that the Australian country singer rest his voice for a week.

"I'm extremely disappointed that I was forced to cancel these appearances," Urban wrote on his website. "But doctor's orders are doctor's orders, and I hope that all those who purchased tickets or who expected me to perform on television will understand that I will make it up to them somehow."

Urban has called off a scheduled Friday (1/24) concert in Indianapolis and a Saturday (1/25) show in Paducah, Ky. He's expected to resume his tour in Owensburo, Ky., on Jan. 31.

On Tuesday (1/21) morning, Urban was scheduled to perform his single "Raining on Sunday" on Good Morning America. That appearance and tapings for The Caroline Rhea Show, the WB Morning Show and AOL Sessions have been called off.

Urban is backing his sophomore album, "Golden Road," which hit stores in October.