An international donors' conference to help Gaza rebuild after the devastating, 50-day Israel-Hamas war this summer has opened in Cairo with participants expected to pledge hundreds of millions of dollars.

Egyptian leader Abdel-Fattah el-Sissi kicked off the one-day gathering Sunday involving envoys such as U.S. Secretary of State John Kerry. Egypt's government negotiated a cease-fire that ended the fighting on Aug. 27.

In his address, Sissi said the reconstruction of Gaza hinged on a "permanent calm" between Hamas and Israel. He said it also required the exercise of "full authority" by the Palestinian Authority, led by Western-backed President Mahmoud Abbas.

The latest Hamas-Israel was the most ruinous of three wars between Hamas and Israel since 2008, leaving more than 2,000 Palestinians, mostly civilians killed. Another 10,000 were wounded, and some 100,000 people remain homeless.