R&B singer/songwriter Robin Thicke, apparently suffering from an unspecified throat or vocal ailment, has been forced to cancel his U.S. tour, which was scheduled to begin this week.

“All tour dates must be rescheduled due to doctor-ordered vocal rest until the end of the year. Thank you for your understanding and support,” he wrote on his website. New dates have not been announced.

The tour was slated to last about a month and wind its way around the country. He was supporting his latest album, the Billboard Top 5 effort, “The Evolution of Robin Thicke.”