Haider al Abadi met with Christian leaders from churches in Baghdad, led by the Patriarch of the Chaldean Church, Primate Raphael Louis I.
During the meeting the Church leaders reminded Prime Minister al Abadi of recent violence towards Christians in some areas of the Iraqi capital, Baghdad.
Primate Raphael told the Catholic news agency Fides: "In the 40-minute talk Prime Minister al Abadi, a Shiite Muslim, repeated several times he personally feels responsible for the protection and defence of Christian citizens also.
"He deplored the phenomenon of the exodus of Christians, defining it as a great loss to the nation.
"With regard to the tragic story of the land fallen under the control of the Islamic Caliphate[I.S.], we urged the Prime Minister to promote in every way the liberation of the occupied lands.
"With much realism he acknowledged that military action will not be enough to solve the problem and that, in the long run, a process that removes the roots of the phenomenon, and brings out the true face of Islam open and respectful of all rights should be encouraged.
"Recently some Christians were kidnapped and some houses of Christian families were attacked by a group of criminals who wanted to occupy them.
"The Prime Minister has promised that he will enhance the presence of military units in the neighbourhoods, and also said he was willing to co-opt another Christian minister in the government.
"I was told me he is a man of word and keeps his promises".
Islamic State has captured various parts of northern and western Iraq while the United States of America has used dozens of air strike to repel the Muslim extremist group.
In September some militants were less than six miles (10km) from Baghdad although they've been pushed back.