But Jan Pronk warned that a much larger force was needed to end the violence in the western Sudanese region.
The AU said troops would start to arrive as part of a 4,500-strong force to be in place by the end of November.
On Friday, the UN said that about 70,000 displaced people were thought to have died in the region since March.
David Nabarro, head of the World Health Organisation’s (WHO) health crisis group, said up to 10,000 people were still dying in refugee camps each month.
