In a letter sent Tuesday, AFSCME President Lee Saunders writes that the UNCF has taken actions “deeply hostile” to public employees, which he considers a “profound betrayal of the ideals of the civil rights movement,” and that the union will end its relationship with UNCF.

Saunders cites the UNCF’s decision to accept a $25 million grant from Koch Industries, Inc. and the Charles Koch Foundation as a reason for the split, as well as the decision by UNCF President Michael Lomax to speak at a summit hosted by the Kochs in California.