The "Islamic State of Iraq and Syria" (ISIS) has lost 95% of the cross-border "caliphate" it declared three years ago in Iraq and Syria, the international coalition fighting it has said.

"Since our coalition was formed in 2014, ISIS has lost 95% of the territory it once controlled in Iraq and Syria," Washington's envoy to the coalition, Brett McGurk, said late Wednesday (November 15th) after a meeting in Jordan.

The terror group swept across Syria and Iraq the same year, declaring a cross-border "caliphate" in territory roughly the size of Britain, attracting thousands of foreign fighters.

But several military offensives, including those backed by the coalition, have since seen ISIS lose most areas it once controlled.

"More than 7.5 million people have now been liberated from ISIS," McGurk said in a statement, adding that the group's finances are now "at their lowest levels to date".

With the group's dreams of statehood lying in tatters following the battlefield defeats, Western attention is increasingly pivoting to trying to block foreign fighters from returning home to carry out attacks.

McGurk insisted that flows of foreign ISIS fighters into Syria have "nearly stopped", and that terror elements are increasingly being picked up as they cross borders.

"We are enhancing co-operation and border security, aviation security, law enforcement, financial sanctions, counter-messaging, and intelligence sharing to prevent ISIS from carrying out attacks in our homelands," he said.