* Muammar Gaddafi family members given refuge in Algeria
* Algeria won't let family harm Libya: new Libyan leader
* NTC chief on fence-building visit to Algeria
By Abdelaziz Boumzar
ALGIERS, April 16 (Reuters) - Libya's leader said on Monday he had obtained an assurance from Algiers that the family of Muammar Gaddafi would be prevented from sabotaging the new Libyan authorities from its refuge in Algeria.
Algeria allowed Gaddafi's wife, daughter and two of his sons to flee onto its territory after a rebellion ended the autocrat's rule last year, infuriating the rebels in Libya who had already accused Algeria of favouring Gaddafi over them.
But speaking after his first visit to Algeria since last year's revolt, Mustafa Abdel Jalil, head of Libya's National Transitional Council (NTC), said he had reached an understanding on the issue with his Algerian counterpart.
"We understand the humanitarian stance that Algeria took to take in the (Gaddafi) family, especially the women and children," Abdel Jalil told reporters after talks with Algerian President Abdelaziz Bouteflika.
"But we remain convinced that it will not give refuge to those who represent a threat to Libya's security... We have reached an agreement that anything that constitutes a threat to Libya, via financing or subversive activities, will not take place on Algerian territory."
He did not specify if the understanding with the Algerian government meant that the Gaddafi family members would eventually be handed over to Tripoli, or allowed to stay but under tight control. Algerian officials made no comment.
REPAIRING TIES
Muammar Gaddafi's wife Safiya, his daughter Aisha, and two of his sons, Mohammed and Hannibal, are in an undisclosed location in Algeria.
Libyan officials at the time described Algeria's decision to grant refuge to the family as an "act of aggression." There was fresh anger from Tripoli when Aisha telephoned a television station from Algeria with messages of support for Gaddafi loyalists inside Libya.
A source who has been in touch with some of the Gaddafi family members in Algeria told Reuters their contacts with the outside world were now subject to tighter restrictions.
The long-running row between Algeria and Libya's new leadership had disrupted security cooperation that Western states believe is crucial to restoring stability to the volatile southern edge of the Sahara desert.
The region is a haven for weapons smugglers and al Qaeda's north African wing, and instability there helped fuel a separatist rebellion in northern Mali.
Abdel Jalil's visit should help draw a line under the two countries' dispute and restore fully-fledged security cooperation.
Security forces from Libya and Algeria have already had talks about sharing intelligence, joint border patrols, and training.
In another step towards normalising ties, Algerian state energy firm Sonatrach is planning to resume its activities in Libya soon, an Algerian energy sector official told Reuters.
Sonatrach, like most foreign energy companies, pulled its staff out during last year's rebellion. Under Gaddafi the company acquired oil and gas exploration rights in the Ghadames basin, near the border between Libya and Algeria.
