Walker asked the Grammy Award-winning singer to instead perform in Gaza. Keys is set to make her first visit to Israel in July and will perform on July 4 as a part of her European tour.
Walker said "it would grieve me to know you are putting yourself in danger (soul danger) by performing in an apartheid country that is being boycotted by many global conscious artists."
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"You were not born when we, your elders who love you, boycotted institutions in the US South to end an American apartheid... Google Montgomery Bus Boycott... We changed our country fundamentally, and the various boycotts of Israeli institutions and products will do the same there."
The author and activist also encouraged Keys to "go to visit the children in Gaza, and sing to them of our mutual love of all children, and of their right not to be harmed simply because they exist."
Keys has not publicly responded to the letter.