A man who works on a tourist cruise boat takes a nap on the river Nile in Cairo April 22, 2013. Most of Egypt's population live clustered around the Nile valley and delta, and the river is both a vital resource for the country's citizens, and a potent national symbol. In a recent dispute with Ethiopia over the construction of a dam upstream, Egypt's foreign minister Mohamed Kamel Amr underlined the country's reliance on the river's waters: "No Nile - no Egypt," he said. Picture taken April 22, 2013. REUTERS/Asmaa Waguih (EGYPT - Tags: POLITICS SOCIETY BUSINESS TRAVEL)

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