The "Islamic State of Iraq and Syria" (ISIS) group's presence in Syria has dramatically declined, with its fighters either on the run or trapped and largely toothless.

On Saturday, the Baghdad government declared the end of a huge military effort that saw Iraqi forces painstakingly reclaim every little piece of the third of the country the extremist group controlled three years ago.

The Syrian side of the "caliphate" ISIS proclaimed in 2014 has disintegrated, with now only gaggles of fighters launching short-lived attacks or clinging to small pockets where they are completely besieged.

ISIS no longer controls a single town in Syria and while it may still count several thousand fighters among its ranks, observers expect Damascus to declare final victory before the end of the year.

On Sunday, French President Emmanuel Macron argued that was slightly premature and predicted that "military operations against ISIS in Syria will continue until mid- to late February".

Rami Abdel Rahman, who heads the Syrian Observatory for Human Rights, said that ISIS was now largely rudderless and that surviving units were essentially fending for themselves.

"There no longer is one central command giving orders. ISIS has been turned into groups scattered over Syria," said Abdel Rahman.

The group's fighters are most active in Syria's eastern Deir Ezzor province, where they are defending the last specks of land that used to be part of their "caliphate".

Several hundred fighters remain in that province alone, not enough to plan any realistic territorial reconquest but enough to cause damage in guerrilla-style attacks.

According to Abdel Rahman, 23 pro-government forces were killed Monday in an attack near Albu Kamal, the last major town ISIS controlled fully before it eventually lost it in November.

Dregs of the caliphate

ISIS still holds 18 villages on the eastern side of the Euphrates river in Deir Ezzor province, according to the Observatory.

It controls a small area in the north-eastern province of al-Hasakeh, and also holds remote areas in the central Homs province, mostly two pockets which the regime is expected to take on soon.

ISIS fighters are also in a small sliver of Hama province, further north, where they are battling extremists from a rival group.

They also have a presence in the Palestinian refugee camp of Yarmuk, in Damascus, but ISIS fighters there have been besieged for years.

The group has fixed positions in two other areas of southern Damascus, Hajar al-Aswad and Tadamun.

In the southern province of Daraa, fighters affiliated with ISIS also have a small presence.

No cohesion

"We will probably witness the end of ISIS as a land-holding force very soon but it will keep existing through sleeper cells," Abdel Rahman said.

As the myriad of anti-extremist forces clawed back land from ISIS over the past three years, thousands of routed extremists are believed to have simply melted back into the desert or blended into civilian life.

"[ISIS] has tried to maintain governance where it exercises formal and full control, but the norm now is functioning as an insurgent group," said Aymen Jawad al-Tamimi, an academic and expert on extremist groups.

The whereabouts and current level of involvement of ISIS leader Abu Bakr al-Baghdadi are unknown. The group no longer has a clear centre of power and its once unstoppable propaganda machine is sputtering out a now anaemic production.

"I am sure there is still a chain of command but the overall structure is likely less cohesive than before," al-Tamimi said.