ISIS could ramp up terror attacks targeting Europe after security experts say the terror group has lost a quarter of its territory to coalition forces in the past 18 months.
The terror group has been driven out of an area the size of Ireland across Syria and Iraq after an sustained assault by government forces.
But defence and security experts are now worried the dramatic reduction in its territory could see the extremists escalate attacks on civilian targets in both Europe and across the Middle East.
According to figures compiled by IHS Conflict Monitor, ISIS controlled territory has dramatically reduced from 35,000 square miles in January 2015 to 26,370 square miles.
Earlier this year, IHS also estimated that ISIS revenue had dropped from £61.7million last year to just £43.2million in March this year.
And now Columb Strack, a senior analyst at IHS, is warning of a change in tact for the terror group.
He explained: ‘Over the past 18 months, the Islamic State has continued to lose territory at an increasing rate.
‘As the Islamic State’s caliphate shrinks and it becomes increasingly clear that its governance project is failing, the group is re-prioritising insurgency.
‘As a result, we unfortunately expect an increase in mass casualty attacks and sabotage of economic infrastructure across Iraq and Syria, and further afield, including Europe.’
The news of the loss of territory for the jihadis comes as Iraqi government forces are preparing for an assault to retake the city of Mosul.
An airbase just outside the northern city has been captured by government forces and is being used by the US military as a place to co-ordinate the battle.
The planned assault comes just weeks after ISIS were driven from the city of Fallujah following a bloody battle.
In March the jihadists were routed from the ancient Syrian city of Palmyra and in June from the Iraqi city of Fallujah.
In 2015, the group lost Tal Abyad, a key border post on the Syrian-Turkish border, as well as the Iraqi city of Ramadi.
In May the Pentagon said that IS had lost some 45 percent of the territory it held in Iraq and between 16 and 20 percent of its territory in Syria.