African Union officials have met separately with Sudan's government and Darfur rebels to draft an agenda for peace talks in Nigeria's capital, Abuja.
Rebels say the agenda is needed to continue political talks with the government, which briefly got under way Tuesday.
Meanwhile, Nigerian military officials say 390 troops are due to leave for Darfur Thursday as part of an expanded AU mission to monitor a cease-fire between rebels and Arab militias.
AU troops from Rwanda also are expected to deploy in coming days.
Also today (Wednesday), a senior United Nations envoy was planning to visit North Darfur to study the government's claim that 70,000 refugees have voluntarily returned home.
The United Nations has threatened sanctions against Khartoum if it fails to improve humanitarian conditions for some 1.5 million refugees.