|The al Nuri mosque site in Mosul has been recaptured from IS|
Haider al Abadi hailed a defeat of the jihadist group after Iraqi troops recaptured the historic mosque - the site where Islamic State announced the creation of their so-called caliphate three years ago.
In a statement, Mr Abadi said: "The return of al Nuri Mosque and al Hadba minaret to the fold of the nation marks the end of the Daesh state of falsehood."
He said Iraqi forces would continue to hunt Islamic State's fighters "to kill them and detain them, down to the last one".
The insurgents blew up the medieval mosque and its famed leaning minaret a week ago as US-backed Iraqi forces advanced towards it.
It was seen as a key symbolic prize in the fight for Mosul.
|Death and despair in battle for west Mosul|
The site will have to be cleared by explosives experts as IS often rigs areas it has retreated from with booby traps.
Although there are about 300 militants still fighting to the death in the Old City district, Iraqi authorities expect the eight-month battle to end within the next few days.
|Officers from Iraq's Counter terrorism Service at the Grand al Nuri Mosque|
IS now holds an area of the west side of the Tigris River less than one kilometre square.
Mr Abadi has already "issued instructions to bring the battle to its conclusion," his office said.
Sky News Chief Correspondent Stuart Ramsay, in Irbil, Iraq, said Mosul had now been taken from IS but there was still a lot of work to do.
He said: "There's a lot of fighting still going on and I think it is likely to go on for a week or two but Mosul has now gone from IS so the end is nigh.
"Geographically it is done but there is still a lot of work ahead."