Kurdish leader Massoud al-Barzani's decision to take down the red-white-and-black flag, which stood alongside the Kurdish flag atop official government buildings in the Kurdish areas of the country, has created further tension between various communities in Iraq.
Kurdish leaders have said the Iraqi flag, with the religious inference added by Saddam Hussein, the former Iraqi president, represents an era of oppression and dictatorship.
They point to the Anfal campaign in which tens of thousands of Kurds were killed by the Iraqi Army.
Barzani had earlier said: "The present flag is not the flag of Iraq, but of the Baath party and chemical strikes, drainage of the marshes, putting down uprisings and mass graves."
But in Mosul, which has a majority Arab population as well as a large Kurdish community, the controversy of which flag to raise has stiffened patriotic zeal and led to an increase in sectarian and ethnic strife.
"The present flag is not the flag of Iraq, but of the Baath party and chemical strikes"
Massoud al-Barzani, Kurdish leader
Many are now wearing pins bearing the Iraqi flag with the religious phrase.
According to Ahmad Fakhry, a political analyst, Mosul residents – particularly those living on the left bank of the Tigris River - have already decided to refuse any other Iraqi flag to represent the nation and are willing to fight if such flags are enforced on them.
He said: "They consider the current flag the last remaining symbol of the unity of the Iraqi people.
"Many in Iraq do not feel changing the flag is a crucial issue at the moment – they would rather focus on how to curb violence, end the occupation, and bring about stability."
'Shroud of martyrs'
One issue that has angered many Iraqis is the fact that the flag was used as an honorary cover for coffins of soldiers and civilians killed during the eight-year Iraq-Iran war.
"They consider the current flag the last remaining symbol of the unity of the Iraqi people"
Ahmad Fakhry, a political analyst
Ibrahim Mohammed, a teacher in a boy's school in Mosul, said: "I am not prepared to forget the history of my brother's martyrdom … he fought in Mhamara [Iranian border town also known as Khoram Shahr] during the war with Iran.
"Does this mean we throw into the sea the sacrifices of those who fought for this country?"
Ethnic violence has also seen a surge as Kurds in some predominantly Arab sectors of the city were forced to leave their homes. Two Kurdish families in the Qadisiya district of northern Mosul fled after unknown gunmen threatened to kill them.
A witness to the evacuation, who refused to be identified for fear of being targeted, said: "Kurdish armed forces surrounded the neighbourhood for four hours as they ensured the family was able to leave safely without being attacked or harassed."
"My colleagues and I have decided to leave the force and take up arms against anyone who is going to take down the flag"
Radhwan Raho, policeman
Members of the Mosul police force are also beginning to weigh in on the issue saying they will not be able to stand by if the Iraqi flag is removed.
Radhwan Raho, who recently completed a police training course, said: "My colleagues and I have decided to leave the force and take up arms against anyone who is going to take down the flag."
But for many residents of Mosul, the issue of the flag transcends Saddam or his government and is more of a question of Arab and Iraqi unity.
Fakhry said: "It isn't only about Iraq, you see, the flag represents Arab unity, the unity of Syria, Egypt and Iraq and is indicative of the greater ideology of an Arab nation.
"If the Kurds insist on raising their national flag, then you will see the Arabs in the north doing the same."