SOUTHERN SHUNEH, Jordan - Islamic State extremists can pose "a very serious threat" to divided Libya if rival governments there fail to reach a unity deal quickly, the United Nations envoy to the North African country said Saturday.

Bernadino Leon, who is mediating political talks, told a regional conference of the World Economic Forum that he hopes for a deal before the start of the Muslim fasting month of Ramadan in mid-June.

Libya has fragmented since the capital of Tripoli was overrun last year by Islamist-allied militias who set up their own government and parliament there while Libya's internationally recognized government withdrew to the east of the country.

The U.N. mediator said his latest draft for a unity deal has been accepted by the eastern-based government, while some in the Tripoli camp have recently come out in support of a national dialogue. He said this has given him some hope a deal might be possible, though he stopped short of saying he was optimistic.

Leon said the rise of Islamic State extremists in Libya "can become a very serious threat for the Libyans" and the international community if unity talks fail. He said extremists have grown from a few small groups six to eight months ago to more than 2,000 loyalists.

Islamic State "has a strong capacity in Tripoli" and a significant presence in Sirte, the birthplace of the late Libyan dictator Moammar Gadhafi, who was ousted and later killed by Libyan rebels in 2011. (AP)