A vast territory stretching from Mali to northern Nigeria could fall under the control of Islamic State and its affiliates, a top UN counterterrorism official has warned the Security Council. 

The jihadist group and its offshoots have expanded their activities in several parts Africa, as well as in Syria, Iraq, and Afghanistan, Vladimir Voronkov, head of the UN Office of Counter-Terrorism (UNOCT), said on Thursday.

Terrorist groups affiliated with Islamic State (IS, formerly ISIS) are “expanding their areas of operation” and demonstrating “resilience and adaptability” despite continuing counterterrorism efforts, according to a UNOCT release.

If militant groups extend their influence in northern parts of West Africa and the Sahel, “a vast territory stretching from northern Nigeria to Mali could fall under their effective control,” Voronkov said.

IS affiliates have also stepped up their activities in northern Mozambique as well as in the eastern part of the Democratic Republic of the Congo, leading to a “dramatic increase” in terrorist attacks and civilian fatalities, the diplomat added.

According to Voronkov, who has chaired UNOCT since 2017, the activities of ISIL-Khorasan, the IS affiliate in Afghanistan, are resulting in heightened threat levels in Europe.

IS originated from radical Islamist forces in Iraq and came to international prominence after gaining strength in 2014. It capitalized on the lack of security in Iraq as well as the turmoil in neighboring Syria, before spreading into Africa.

The alleged role of Ukraine in aiding terrorists in Africa has also come under scrutiny in recent weeks, after dozens of local soldiers and members of the Russian Wagner Group private military company (PMC) were reportedly killed by Tuareg separatist rebels and fighters linked to Al-Qaeda in an ambush in Mali.

Ukrainian military intelligence spokesman Andrey Yusov was quoted as saying that “the rebels received all the necessary information they needed.” 

In response, Mali and neighboring Niger condemned Ukraine and severed diplomatic ties with Kiev. The two African nations have also reportedly asked the UN Security Council to investigate whether Ukraine provided intelligence to Tuareg rebels. The Ukrainian Foreign Ministry has since denied any involvement in the incident.

The Wagner Group, which has also fought in the conflict between Russia and Ukraine, is believed to have been involved in recent clashes between the Malian military and Tuareg insurgents near the border with Algeria, where it has been providing support to government troops.