Nicki Minaj has caused controversy and upset fans and a charity, after she announced she will headline a concert in Angola.

The 33-year-old rapper is due to headline a Christmas festival in the capital of Luanda on Saturday (19.12.15), titled Show Unitel Boas Festas.

But Angola’s government has been accused of oppression, intimidation and imprisoning supporters of democracy, and the Human Rights Foundation has written to the the ‘Anaconda’ singer to ask her to cancel her performance.

Thor Halvorssen, head of the non-governmental organisation, recently wrote in a letter to the star: “Ms. Minaj, you are well known for being involved with charities such as the Get Schooled Foundation, which helps motivate young people to graduate from high school and succeed in college. If you move forward with this performance for the dictator and his family, you will be in league with the people stealing educational resources and opportunity from young Angolans.”

Halvorssen also highlighted the case of Angolan hip hop artist Luaty Beirao, who was arrested in June after attending a meeting that discussed democracy in the country.

And since Angola’s President Jose Eduardo dos Santos has been accused of corruption in the past, fans have rallied together and protested against the singer’s decision to accept the country’s invitation to play.

One wrote via her official Facebook page: “Dear Nicki Minaj, could you please postpone your visit to Luanda until democracy is born in Angola?”