Eleven AU peacekeepers were held hostage Tuesday evening in Um Kaddada town in the northern Darfur state by the Sudan Liberation Movement (SLM), one of the two major rebel groups in Darfur.
A representative of the other major rebel group, the Justice and Equality Movement (JEM), was also kidnapped.
The kidnappers demanded an AU representative meet them for talks over the release of the hostages, but a bad weather condition hampered the mission.
The kidnapped soldiers, whose nationalities were not revealed, are among the 2,200 AU troops deployed in the war-plagued western region of Darfur to monitor a ceasefire between the warring sides.
The AU agreed to beef up its forces in Darfur to 7,700 in April, after the Sudanese government approved logistic support from the North Atlantic Treaty Organization (NATO) to the AU forces in Darfur.
The Sudanese government refuses any presence of non-African forces in Darfur, where thousands of people have been killed and over one million displaced since rebels took up arms against the government in February 2003, accusing it of neglecting the barren area.
The Sudanese government has said it is ready to resume peace talks with two main Darfur rebel groups in the Nigerian capital Abuja. Previous talks have failed to bring major breakthrough.