Al-Baghdadi's speech came amid reports that Daesh commanders based in the western part of Iraq's Mosul are fleeing the city.
"Calling his speech a farewell address, al-Baghdadi circulated it among Daesh preachers and explained what was going on with the group. The preachers started talking about the defeats Daesh is suffering in Nineveh province and other parts of Iraq," the source said.
On Monday, Mahmud al Surdji, a representative of Iraq's Nineveh Plain Protection Units told Sputnik Arabic that government forces had taken full control of the highway connecting Mosul and the capital Baghdad.
According to him, forces from the 9th Armored Division have encircled the Daesh terrorists near Mosul's largest electric power plant, on the west bank of the Tigris River.
He said that later this week, the Iraqi army is planning to finish its operation to free the Wadi Hajar neighborhood.
He added that the liberation of this particular district will provide the army with access to other districts of the city which still remain under Daesh control.
Last Sunday, Iraqi Prime Minister Haider Abadi announced the start of operations to liberate the western part of the city.
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