"Our forces are in complete control of the Iraqi-Syrian border and I therefore announce the end of the war against Daesh (ISIL or ISIS)," Abadi told a conference in Baghdad, AFP reported.
"Our enemy wanted to kill our civilization, but we have won through our unity and our determination. We have triumphed in little time," he said.
Daesh seized vast areas north and west of Baghdad in a lightning offensive in 2014, endangering the very existence of the Iraqi State.
"I announce the good news: the liberation by Iraqi forces of the whole of the Iraqi-Syrian border," the prime minister told the conference organized by the Iraqi journalists' union.