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TRIPOLI, April 24 (Reuters) - U.S. Deputy Secretary of State William Burns on Thursday promised Libya more U.S. help against extremist violence, saying the country could not achieve political or economic stability without tackling its security challenges.
Libya's weak central government is struggling to assert its authority against militias and armed tribesmen who helped oust Muammar Gaddafi in a 2011 NATO-backed uprising.
"Rising violent extremism is an enormous challenge first for Libya but also for Libya's international partners," Burns told a news conference after talks in the capital Tripoli.
"That's why we have a such sense of urgency and such a sense of determination to help Libyans build their own security capacity, to deepen counter terrorism cooperation and also to promote the kind of healthy political process ... that increases the chances of greater security over the long-term," he said.
Burns is the most senior United States official to visit the oil-producing nation since an Islamist militant attack on Washington's consulate in the eastern Libyan city of Benghazi in September 2012 in which the U.S. ambassador and three other Americans were killed.
Burns said rebuilding security was key to Libyan success.
"It is impossible to foresee the successful political transition and successful economic revival without a greater sense of security," Burns said.
He did not elaborate on how Washington would deepen its security cooperation with Tripoli, repeating only that the United States and other partners would continue to train Libya's nascent army and security forces. (Reporting by Ulf Laessing, Writing by William Maclean; Editing by Gareth Jones)