In the audio recording, entitled A Message to the People of Iraq, bin Laden called on tribal leaders and the leaders of armed groups to initiate an agreement between the different groups.
"The interest of the Islamic nation surpasses that of a group," he said.
"The strength of faith is in the strength of the bond between Muslims and not that of a tribe or that of nationalism."
Bin Laden said fighters in Iraq should admit "mistakes" and try to correct them in the interest of unity.
The recording was aired as Iraq's government reported violence had dropped by 70 per cent since the end of June, following a series of US-led offensives.
Iraq's wing of al-Qaeda is one of the groups fighting US-led forces and the Baghdad government, but bin Laden's followers have angered other Sunni groups and tribes through their interpretations of Islam and indiscriminate killing of civilians.
"The mujahidin are the children of this nation ... they do right things and wrong things," bin Laden said. "Those who are accused of violations of God's commandments should face trial," bin Laden said.
In the recording, bin Laden mentioned battles in the province of Diyala, indicating that he made the remarks since the start of a US offensive there in June.
He said he was addressing "mujahidin [holy warriors] in Iraq", Sunni Muslim groups fighting US-led forces.
Last month, bin Laden issued three messages, including a video marking the September 11, 2001, attacks on New York and Washington in which about 3,000 people were killed.
Bin Laden said in the video that the United States was vulnerable despite its power and insisted only conversion to Islam would end the conflict.
Phil Rees, who has written on al-Qaeda, told Al Jazeera: "I think there's always been a tension between the leadership [of al-Qaeda], wherever that is ... and elements such as, say, Abu Musab al-Zarqawi.
"We know there were various communications condemning some of the sectarian attacks and feeling that al-Zarqawi was something of a loose cannon."
He said the tape could be an attempt by bin Laden to re-establish control over Sunni fighters in Iraq.
"Maybe its a sign that he is in charge and he is trying to rein in these people," he said.
In recent months Sunni tribal groups have formed alliances and worked with US forces to confront al-Qaeda in Iraq.