FEARS are growing for the health of 77-year-old singer Sir Tom Jones after "medical advice" forced him to postpone his US tour.

The crooner offered his "sincere apologies" to fans in a post on Twitter in which he said dates were being rescheduled for next year.

The Voice star made the announcement five days before the scheduled start of the run of concerts which would have taken him to Pennsylvania, New Jersey, Colorado, Texas and California.

A statement, also posted on the It's Not Unusual singer's website, did not give details about his health issues. It said: "Following medical advice, Sir Tom Jones has announced that he will unfortunately be postponing his US tour, which was due to commence in Bethlehem, Pennsylvania, on Wednesday September 6.

"Dates are being re-scheduled for May and June 2018 and all tickets will remain valid for the new dates, details of which, will follow as soon as possible.

"Tom sends his sincere apologies to his fans and looks forward to seeing them all again in 2018."

The Welsh star was left devastated by the death of his wife of 59 years, Linda, last year following a battle with cancer.