"The recent expansion of the ISIL sphere of influence across West and North Africa, the Middle East and South and South-East Asia demonstrates the speed and scale at which the gravity of the threat has evolved in just 18 months," Ban said in a report to the UN Security Council.

In Afghanistan and Pakistan, ISIL continues to develop a network of contacts and sympathisers who carry out attacks in its name, Ban said in his report which was submitted to the Security Council by Jeffrey Feltman, the Under-Secretary-General for Political Affairs during a debate on the threat posed by ISIL - also known as Daesh - to international peace and security, Times of India reported.