The collective will release 'Never Let Me Go' on April 2.
Discussing the song, Florence Welch said: "The gospel thing comes from my obsession with hymns. I'm drawn to anything that has a hymnal quality, be it Spiritualized or dusty old albums by Georgian choirs."
The track, which was co-written by Welch and produced by Paul Epworth (Adele), marks the third cut from her latest album Ceremonials.
The release follows 'No Light, No Light' and 'Shake It Out', which peaked at number 12 on the singles chart last year.
The singer recently picked up two gongs at this year's NME Awards, for 'Best Solo Artist' and 'Best Song'.
> Florence + the Machine announce US tour dates for Ceremonials album
Listen to 'Never Let Me Go' below: