The Human Rights Foundation has asked Nicki Minaj to cancel an upcoming concert in Angola, where she is scheduled to perform on Saturday as part of a Christmas festival sponsored by Unitel. Unitel is a communications company controlled by the family of Angolan President José Eduardo dos Santos, who is accused of “[exploiting] Angola’s diamond and oil wealth to amass an illegitimate fortune while maintaining control over all branches of the government, the military, and civil society,” according to an open letter sent by HRF president Thor Halvorssen to Minaj and her management.

The Robert F Kennedy Human Rights group has also criticized her appearance at the show. Their African Policy Director Jeffrey Smith told New York Daily News that she was “callously taking money from a dictator who’s been in power for nearly four decades and who has effectively and ruthlessly choked free expression, setting a horrible precedent not only for Angola, but for the entire region.”

The Guardian points out that Mariah Carey faced similar protests after she performed for the Dos Santos family back in 2013, and earned an alleged $1 million. After the performance, she said she was “naive and unaware of who I was booked to perform for,” and noted that it was “a lesson for all artists to learn from.”

Minaj has not yet responded.