Keys cancels two concerts on tour

Alicia Keys also cancelled dates in her European tour in February

Singer Alicia Keys has cancelled two shows on her North American tour because of swollen vocal cords, her record label has confirmed.

The 27-year-old has scrapped her Pittsburgh show and a gig in Cleveland.

A statement posted on her website said she is "currently being treated by a physician" and is expected to return to the stage on Saturday in Columbus.

This comes days after her support act, American Idol winner Jordin Sparks, pulled out because of vocal problems.

Laryngitis

This is not the first time illness has forced Keys to pull out of concert dates.

At the time the Grammy-award-winning singer's publicist said she was suffering from laryngitis.

In February the singer postponed two concerts on her European tour after her doctor told her to rest her voice.

Meanwhile a statement released on behalf of Sparks' record company 19/Jive Records said: "Jordin Sparks is on vocal rest and is expected to make a full and complete recovery.

"Sparks has been going non-stop over the past two years and now she's going through the normal course of learning how to manage and care for her voice."

The 18-year-old is expected to rejoin Keys in May.