The al-Qaeda-linked group of infamous one-eyed Algerian fighter Mokhtar Belmokhtar has pledged allegiance to the Islamic State (Isis) according to an audio aired by private Mauritanian agency al-Akhbar.
Adnan Abou Walid Sahraoui, a leading member of the al-Murabitoun movement vowed loyalty "to the caliph of Muslims Abu Bakr al-Baghdadi, thereby banishing divisions and dissent within the nation".
It is unclear whether Belmokhtar, whose terrorist cell led a deadly raid in Algeria's Amenas gas in January 2013 killing 37 oil contractors, took part to the oath.
Dubbed "The Uncatchable" or "Mr Marlboro", because of his role in cigarette-smuggling across the Sahel, Belmokhtar is a former al-Qaeda in the Islamic Maghreb (AQIM) member and is on the wanted list for masterminding the In Amenas BP gas plant siege in which 37 people, including six Britons, were killed.
Belmokhtar, who formed his own militia in 2012, is also accused of organising two suicide attacks in Niger, targeting a military base in Agadez and the French-run uranium mine in Arlit that killed at least 25 people.
His militia joined ranks with another al-Qaeda spinoff, the Movement for Oneness and Jihad in West Africa (MUJAO) Mujao to form a group known as al-Murabitoun, which has pledged to take revenge against France for its military campaign in Mali.
In January, Belmokhtar praised the Paris shooting at French satirical magazine Charlie Hebdo and urged Muslims to carry out similar attacks.
He called the Kouachi brothers, who killed 12 people in the Paris office of Charlie Hebdo, "our best knights".