Aretha Franklin has undergone “highly successful” surgery at a hospital in Detroit.

The 68-year-old soul singer, who has cancelled her upcoming appearances, has not stated what she is being treated for.

In a statement, Franklin thanked fans who had gathered outside the hospital on Wednesday (December 1) to say prayers.

She also paid tribute to the medical staff "whom were blessed by all the prayers of the city and the country".

Last month, the singer axed all gigs for the next six months under the orders of her doctors, but said she was "anxious" to get back on the road.

Franklin’s cancelled gigs include a planned Christmas gig in Detroit.

In August, the singer, whose hits include 'Say A Little Prayer', broke two ribs during a fall.

(by Jason Gregory)