Libyan Prime Minister Abdurrahim al-Keib called on Sunday for a regional security conference to tackle a proliferation of weapons by exiled supporters of former leader Muammar Gaddafi.

The Libyan civil war may have given militant groups in Africa's Sahel region like Boko Haram and al Qaeda access to large weapons caches, said a U.N. report released on Thursday.

(There is) still a real threat from some of the armed remnants of the former regime who escaped outside the country and still roam freely. This is a threat for us, for neighbouring countries and our shared relations, Keib told African Union leaders in Addis Ababa.

My country calls for a regional security conference in Libya of interior and defence ministers of neighbouring countries, he told the summit, the first since Gaddafi's death last year.

A U.N. report said the Libyan civil war may have created a proliferation of small arms, giving militant groups like Boko Haram and al Qaeda access to large weapons caches in Africa's Sahel region that straddle the Sahara, including Nigeria, Niger and Chad.

The report said some countries believe weapons have been smuggled into the Sahel by former fighters in Libya - Libyan army regulars and mercenaries who fought on behalf of Gaddafi, who was ousted and killed by rebels.

Links between al Qaeda and Boko Haram have become a growing source of concern for the countries of the region, the U.N. report said.

The Islamist sect Boko Haram has killed at least 935 people since it launched an uprising in Nigeria in 2009, including 250 in the first weeks of this year, Human Rights Watch said last week.

(Reporting by Yara Bayoumy; Editing by James Macharia)