UNITED NATIONS — Jan Kubis, the top UN envoy for Libya, has resigned only a month before the country is going to hold crucial parliamentary and presidential elections, the world body said on Tuesday.

Kubis decided to step down after just 10 months in the job. With the presidential vote set for December 24, the UN is “working as quickly as possible to ensure continuity of leadership,” spokesperson Stephane Dujarric said at a news briefing at UN headquarters.

“I can tell you Kubis has tendered his resignation and the secretary-general has accepted it with regret,” Dujarric said.

He didn't give a reason for Kubis' resignation, but said the envoy didn't have any falling-out with Secretary-General Antonio Guterres.

The Geneva-based Kubis is still expected to brief the UN Security Council on Wednesday, as scheduled before his resignation, the Associated Press reported.

Kubis, a former Slovak foreign minister who previously held high-level UN posts in Iraq and Afghanistan, became the head of the UN political mission in Libya in January, after the world body sought for nearly a year to fill the sensitive job. One leading candidate turned it down, some UN member countries objected to other suggestions and there were changes in the job itself.

Libya plunged into turmoil after a NATO-backed uprising in 2011 toppled dictator Moammar Gadhafi, who was later killed. The oil-rich nation then became divided between rival governments — one in the east, backed by military commander Khalifa Hifter, and a UN-supported administration in Tripoli. Each side is backed by different militias and foreign powers.

UN-mediated talks led early this year to the formation of a transitional government intended to lead the country to the December elections. Hopefuls include Hifter, Ghadafi's son Seif al-Islam, former interior minister Fathi Bashagha, parliament leader Aguila Saleh and interim Prime Minister Abdul Hamid Dbeibah, who filed a request to run despite rules barring him from doing so.

Kubis has emphasized the election's importance.

“Holding the elections in Libya, even in less-than-ideal situation, and with all imperfections, challenges and risks, is much more desirable than no elections,” he told the Security Council in September. “That could only foster division, instability and conflict.” — Agencies