Jeffrey Feltman, the UN under-secretary of state for political affairs, will also travel to neighboring Tunisia during his visit until Friday, said a UN statement.
The United Nations has launched a plan to bring stability to Libya through elections and changes to a 2015 political deal that set up a government of national accord led by Prime Minister Fayez al-Sarraj.
After two meetings were held in Tunis last year, there appears to have been little progress.
“The United Nations urges all Libyan actors to engage in earnest in an inclusive political process leading to credible and fair elections,” said Feltman.
There is a “window of opportunity” to focus efforts on building unified state institutions, he added.
Feltman’s itinerary was not released for security reasons, but sources said he planned to meet with Khalifa Haftar, the powerful leader whose Libyan National Army dominates the country’s east.
He is also expected to hold talks with Sarraj and Aguila Saleh Issa, the parliament speaker based in the eastern town of Tobruk who opposes the UN-backed administration.
Despite the 2015 accord, Libya remains divided between the UN-backed government in Tripoli and a rival administration in the east that enjoys support from Egypt, Russia and the United Arab Emirates.
One of the main stumbling blocks is inclusion in Haftar’s new government.
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