UNITED NATIONS (AP) — Secretary-General Ban Ki-moon has appointed Spanish diplomat Bernardino Leon to head the U.N. political mission in Libya, which is witnessing its worst spasm of violence since the 2011 ouster and killing of dictator Moammar Gadhafi.

U.N. spokesman Stephane Dujarric, who announced the appointment Thursday, said Leon "brings to this position many years of political and diplomatic experience."

He will succeed Tarek Mitri as the secretary-general's special representative in the troubled north African country on Sept. 1.

Leon has worked extensively on Middle East issues. He served as the top foreign policy adviser to Prime Minister José Luis Rodríguez Zapatero from 2008-2011 and is currently the European Union's special representative for Libya and for the southern Mediterranean.