NEW YORK - Top Hollywood stars Angelina Jolie and Brad Pitt have donated $1 million to help displaced people in Pakistan, a country the actress has visited thrice as United Nations refugee agencys goodwill ambassador. The Oscar-winning actress took Pitt with her on one such visit to Pakistan in 2005. Now in support of Jolies eight-year relationship with the Geneva-based United Nations High Commissioner for Refugees (UNHCR), the couple decided to take this step, reported The UNHCR head, Antonio Guterres, thanked the foundation for its assistance, calling Pakistans plight the most challenging humanitarian crisis of the past decade, as more than 2 million people are currently displaced in the country. APP adds: Jolie will celebrate World Refugee Day in Washington on Thursday with Secretary of State Hillary Clinton. The UNHCR, this week, made an impassioned appeal to the rich countries to contribute generously to the massive Pakistani relief efforts underway. In response to President Barack Obamas request, the Congress is close to approving another $ 225 million in this regard. The UN officials appealed for $500 million to $600 million about two weeks ago when the number of the IDPs stood at 1.5 million but the refugee agency estimates the relief activities would now require more financial assistance to carry out its operations.