(CNN) -- Al Jarreau's newest audience is the medical staff at a cardiac center in Marseille, France, where the singer is undergoing tests after becoming "weak from the altitude" in the French Alps last week.
Jarreau, 70, was transferred to Marseille over the weekend from a hospital in Gap, France, where he was taken after he fell ill in the resort town of Barcelonnette in the southern French Alps on Thursday, his publicist said.
The latest report from the singer's publicist does not reveal any other details about his illness, which forced the cancellation of shows in Germany, Azerbaijan and France.
"Mr. Jarreau hopes to resume his tour at the end of the coming week," according to a statement posted on his website Sunday. "Meanwhile, he has been quietly serenading the hospital staff to stay on point."
Jarreau's next concerts are set for Nuremberg, Germany, on Thursday and Gleisdorf, Austria, on Friday, according to the tour calendar on his website.