Pakistani officials say the death toll from floods caused by heavy monsoon rains has risen to more than 800, and rescue workers are struggling to reach thousands of stranded villagers.
People here say the last four days of pounding rain have inundated Pakistan's northwest, while in Afghanistan's east and northeast 64 people have died.
Afghan and NATO forces said they were using helicopters to conduct rescues as well as distribute aid to the the worst affected regions of Afghanistan, including Kunar and Nangahar provinces.
Meanwhile, the U.N. estimated Saturday that some 1 million Pakistanis have been affected by the disaster, with thousands of homes, roads and farms destroyed.
About 45 bridges were damaged around the Khyber-Pakhtunkhwa province, while the main highway to China remains under water.
Television footage showed scores of men, women and children sitting stranded on top of roof in hopes of air or boat rescue.
Pakistan Provincial Information Minister Mian Iftikhar Hussain has appealed to the international community for assistance, calling it the deadliest flooding to hit the country since 1929.
Meteorologists say more rain is expected in the coming days.