About 7,000 peacekeepers from the 26-nation African Union are currently posted in the war-torn region, but they will be replaced with 26,000-strong joint units of the African Union and the UN by the end of the year.
Previously, Sudan had refused to accept a UN peacekeeping contingent. But the country changed its position after an African tour of UN Secretary General Ban Ki-moon, who also secured an agreement to hold peace talks on Darfur in Libya on October 27.
In March 2007, the UN accused Sudan's government of orchestrating and taking part in "gross violations" in Darfur, and called for urgent international action to protect civilians.
Since the conflict began in February 2003, ethnic violence has taken the lives of at least 200,000 people, mostly among black African farmers, from which rebel groups fighting the central government in Khartoum draw their numbers, the UN says.
Armed militias known as "Janjaweed," which the Sudanese government denies supporting and who continue to attack civilians, are largely nomadic Arabs, and have been involved in violent battles with farmers over land ownership.
