UNHCR Goodwill Ambassador Angelina Jolie has issued a plea for humanitarian relief for the victims of Pakistan’s floods, which have devastated much of the country.

Angelina has made three visits to Pakistan since 2001, when she became a UNHCR Goodwill Ambassador, and donated $100,000 to qwell the current crisis.

“One-fifth of Pakistan is under water and the threat of disease now looms for 20 million affected people,” the Academy Award winner remarks in a public service announcement issued by the United Nations on Tuesday. “This is not just a humanitarian crisis; it is an economic and social catastrophe. UNHCR is on the ground. The more support we can give, the greater number of tents, food, clean water, and medicine will get to the people in need.”