Florence and The Machine have pulled out of two European concerts because the lead singer has lost her voice and been told not to perform to avoid permanent damage.

Florence Welch explained the situation on her Twitter account Wednesday.

The British band was due to play at the Benicassim festival in Spain on Thursday and at the Optimus Alive event in Portugal this weekend.

As well as passing on her apologies to fans, Welch tweeted about what happened, saying: "I cannot sing for a week... seriously I felt something snap, it was very frightening."

The flame-haired Welch fronts the Grammy-nominated seven-piece band, which released its latest album, "Ceremonials," last year.