(REUTERS) - The influence of the Islamic State in Iraq and Syria (ISIS) is gradually expanding from its stronghold in the Middle East to extremist groups in North Africa.

Militants in several countries in North Africa, including Libya, Egypt, Algeria and Tunisia, have pledged allegiance to ISIS leader Abu Bakr al-Baghdadi.

ISIS-affiliated militant groups have divided Libya into three regions and have a presence in the capital of Tripoli and coastal cities Darnah and Benghazi. The radical Oqba ibn Nafaa brigade in Tunisia has also spoken out in support of ISIS, and many Tunisian ISIS recruits pass through Libya for training.

And in Egypt's Sinai Peninsula, the Al-Qaeda-inspired group Ansar Beit al-Maqdis, has declared itself the Sinai Province of the Islamic State.

Algerian islamic group Jund al-Khilafah also declared its allegiance to al-Baghdadi. However, the Algerian government has captured or killed most of its members during a massive operation against the group.

European states closest to Libya are watching in growing alarm as militants affiliated with ISIS have risen to prominence across North Africa.

Italian Premier Matteo Renzi has asked for the United Nations' assistance to combat the growing reach of ISIS-affiliated extremist groups in Libya, which is just 800km away from Italy.