Jolie gave birth to daughter Shiloh Nouvel in May

In a statement, Jolie said: "I have seen these brave men and women working in war zones and horrific conditions and I deeply admire them."

Both groups, Global Action for Children and Medecins Sans Frontieres, aim to improve life for people living in poverty in troubled areas of the world.

In June, the pair sold photos of their new baby to raise money for charity.

Experts estimate that the global rights to the first images of the couple with their daughter, Shiloh Nouvel, will have raised as much as $7m (�3.75m).

The Hollywood couple also donated $300,000 (�160,000) towards maternity equipment in Namibia, where Shiloh was born.

Both organisations benefitting from the couple's most recent donation thanked the pair for their generosity.

Their generous gift will enable us to continue assisting people whose plight is often forgotten Nicolas de Torrente, executive director of Doctors Without Borders

Jennifer Delaney, of Global Action for Children, said: "Angelina Jolie and Brad Pitt not only care, but more important, are taking concrete action to address the fact that there will be 20 million children orphaned by AIDS by 2010 and millions orphaned by tuberculosis, malaria and conflict."

"Their generous gift will enable us to continue assisting people whose plight is often forgotten, such as those displaced by conflict in the Democratic Republic of Congo or Sudan," said Nicolas de Torrente, executive director of Medecins Sans Frontieres.

Jolie, 30, has travelled to more than 20 countries in her role as a goodwill ambassador for the United Nations since 2001.