Tindouf (Algeria) (AFP) - UN Secretary General Ban Ki-Moon on Saturday visited a camp in Algeria for refugees from the Western Sahara territory disputed between Morocco and the Polisario Front group.

Algeria is the main supporter of the Polisario Front.

Ban arrived from the Mauritanian capital Nouakchott, where he also warned that the future of Libya, and the stability of the whole Sahel region, is at stake as it faces the "terrifying threat" of the Islamic State group.

The UN chief's visit to both countries is part of a tour of West and North Africa.

Ban, who met Polisario Front leaders including its Secretary General Mohamed Abdelaziz, said he would "spare no effort" in trying to find a solution to the Western Sahara issue.

The UN chief said warring factions had failed to make "any progress towards a solution" to a conflict that has lasted 40 years.

He began his visit at the Smara refugee camp near Tindouf 1,800 kilometres (1,100 miles) west of Algiers near the border with Morocco and was greeted by a crowd of several thousand.

Ban said that refugee camps built in Algeria more than four decades ago and which currently shelter near 200,000 people "are among the oldest in the world".

He voiced sadness that people have been trapped there for so long, and added that the United Nations will strive to improve conditions for the refugees.

The UN has been trying to oversee an independence referendum for Western Sahara since 1992 after a ceasefire was reached to end a war that broke out when Morocco sent its forces to the former Spanish territory in 1975.

Tens of thousands of refugees from Western Sahara live in refugee camps in Algeria, which were built when the fighting began.

Ban also visited a UN base at Bir-Lahou in the disputed territory.

In Nouakchott on Friday, Ban also called for Mauritania's help in the Western Sahara dispute.

"Making progress on the situation in Western Sahara is also of importance here too," he said. "Numerous refugees share the same culture and family ties with Mauritanians."

He also said he was "deeply concerned about the situation in Libya".

Chaos has engulfed Libya since the 2011 NATO-backed ouster of dictator Moamer Kadhafi and rival administrations are being urged to sign up to a UN-brokered national unity government to help restore stability.

The internationally recognised government is based in the far east of the North African country.

The Islamic State group and other extremist organisations have exploited the power vacuum, making gains along the oil-rich coastal regions and triggering concern among Western nations over jihadists controlling territory just 300 kilometres (185 miles) from Europe.

Success in stabilising Libya would also benefit the whole Sahel region and "our world" in general, Ban said.