Kelly Clarkson has cancelled the upcoming Canada and U.K. dates of her ‘Piece by Piece' tour following problems with her voice.

The U.S. star has been told by doctors that she needs to rest her vocal cords until the end of the year, NME reports.

The hitmaker broke the news to her fans with a Twitter statement describing her disappointment. She had already been forced to cancel six U.S. dates earlier this month.

Cities she had been scheduled to play in this November include Glasgow, Leeds, Manchester, Birmingham and London.