The last major town held by Islamic State in Syria was reported to have fallen to government forces on Wednesday night, leaving the terror group near complete collapse.

The offensive to retake Albu Kamal in eastern Syria was launched several days ago after regime troops and allied militias, under the cover of Russian airpower, captured the last Isil-held city of Deir Ezzor.

On Wednesday fighters from the Iran-backed Iraqi Popular Mobilisation Unit (PMU) crossed the frontier to squeeze the group from the east.

Its commander announced the complete liberation late last night, but there was no immediate confirmation from the Syrian government.

Isil, which once controlled a “caliphate” the size of Britain spanning Iraq and Syria, has lost more than 95 per cent of its territory.