The addition would bring the number of AU soldiers and police in Darfur to 11,000.
The announcement comes just days after the Addis Ababa, an Ethiopian based organization, said it would extend its mission in the strife-torn region by three months.
"The Peace and Security Council of the AU ... has endorsed the new concept of operation, extending the duration of stay of the African Mission in Sudan up to Dec. 31, 2006, and to boost the troop level by six battalions," said Assan Ba, an AU spokesman, according to Reuters.
The AU will send soldiers from countries already serving in Darfur, including Nigeria, Rwanda, South Africa and Senegal, the news service reported. The force will get logistical support from the United Nations and funding from Arab states.
Peacekeeping troops have been in Darfur since 2005, more than two years after violence between government forces and Darfur rebels erupted. An estimated 200,000 people have died since then and 2.5 million have been forced from their homes into squalid displacement camps in Sudan and Chad.
Despite a peace deal signed in May, violence continues to plague the region and humanitarian groups estimate many thousands more could die if additional help does not arrive.
The current AU force has been incapable of quelling the violence, in part due to limited resources and funding.
In August, the U.N. Security Council voted to send 22,500 U.N. troops to Darfur to bolster the AU force, but Sudan's government has refused such a deployment, claiming a U.N. presence would amount to colonization.
"[The United Nations] wants to make a pretext through the Darfur issue to control us and to recolonise Sudan," Sudanese President Omar al-Bashir said during a news conference in Khartoum on Monday, according to Reuters. "These powers are imperialistic. We have to act to abort all this aggression against Sudan, all this plotting against Sudan."
Representatives of the Security Council, in a rare delegate trip, visited Sudan in June to lobby al-Bashir. South African President Thabo Mbeki also has approached Sudan's government in an effort to change officials' minds.