BRUSSELS (Reuters) - The European Union on Thursday extended its civilian mission in Libya by a year and allocated a $18.92 million budget for the task.

Set up in May 2013, the Tunis-based body's mandate has been extended several times, with the last due to expire on Aug. 21. It aims to provide advice to Libyan authorities on migration, border security, counter-terrorism and criminal justice issues.

EU foreign ministers in May agreed to help Libya rebuild its shattered navy and coastguard to tackle migrant smugglers in respond to a request from the new U.N.-backed unity government in Tripoli.

Libya is a major departure point for mainly sub-Saharan African migrants looking to reach Europe in flimsy boats arranged by people smugglers. The flow of migrants has increased in the turmoil following the 2011 uprising that toppled Muammar Gaddafi.

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(Reporting by Foo Yun Chee; Editing by Richard Balmforth)