Maliki spoke to the officers in the city of Samarra and told them that volunteers were arriving to help defeat rebels.
"We are not sectarian, we will fight as a nation," Maliki said in the speech, which was shown on state television on Saturday.
"We will talk the language of justice, we will talk the language of freedom, we will talk the language of all Iraqis regardless of their sect."
Maliki said the cabinet had granted him unlimited powers to confront the fighters from the Islamic State in Iraq and the Levant (ISIL) and associated rebel groups, Al Jazeera reported.
"Samarra will not be the last line of defence, but a gathering point and launchpad," Maliki told officers in the city, which lies about 125km north of the capital on the road to rebel-controlled Mosul.
Within the coming hours, all the volunteers will arrive to support the security forces in their war against the gangs of ISIL, Maliki, who leads the government, said. "This is the beginning of the end of them."
Grand Ayatollah Ali al-Sistani, Iraq's most influential Shia cleric, had also urged people on Friday to take up arms and defend the country.