The couple’s non-profit organisation the Jolie-Pitt Foundation has given the generous sum to the Human Rights Watch’s work in Burma and Zimbabwe.

Kenneth Roth, Human Rights Watch’s executive director, welcomed the donation, saying: "Burma and Zimbabwe are two of the most repressive countries in the world and we need to increase international pressure on them to change.

"Brad and Angelina's investment in our work at this critical moment will allow intensified efforts by our researchers to expose the repression that these governments try to keep hidden and by our advocates to generate the global pressure needed to improve people's lives."

Brad, 44, and 33-year-old Angelina’s contribution will go towards funding research and advocacy in the two countries.

The Human Rights Watch is an independent organisation dedicated to exposing human rights violations and protecting people at risk of discrimination throughout the world.

Earlier this month, the generous duo - who have six children together - handed over US$2 million to fund a children’s home in Ethiopia. Their adopted three-year-old daughter Zahara was born in the African country.

The couple also run a health centre in Cambodia, where their seven-year-old son Maddox was born. In June, the Jolie-Pitt Foundation donated US$1 million to children affected by the Iraq war.