Hadi, who stood as the sole candidate to replace Saleh in a US-backed power transfer deal brokered by Gulf neighbours, was voted in after more than 60 percent of eligible voters had taken part in the election this week. Saleh's departure makes him the fourth Arab autocrat to be removed from power in more than a year of mass uprisings and war that have redrawn the political map of the Middle East. After taking the oath, Hadi said in a speech that Yemen must draw a line under the crisis and tackle pressing issues such as a deepening economic crisis, and bringing those displaced by Yemen's crisis back to their homes. "If we don't deal with challenges practically, then chaos will reign," Hadi said. Yemen's richer neighbours, led by Saudi Arabia, crafted the power transfer, also backed by Washington and a UN Security Council resolution, to ease out Saleh, who had ruled Yemen for 33 years.