UN Secretary-General Kofi Annan has called a high-level international meeting later this week to discuss the peacekeeping crisis in Sudan's Darfur.
More than two million people have been displaced during the conflict
Some 7,000 African Union troops have not halted the violence. Mr Annan wants a bigger UN role in a hybrid force.
In Darfur at the weekend, some 30 people were killed, when pro-government militias raided a village near Chad.
The UN has offered $77m to help the AU - but needs Sudan's approval to change the structure of the force.
Mr Annan has asked the five permanent Security Council members, as well as the European Union and the Arab League, to attend Thursday's talks in Ethiopia.
Sudan has resisted plans for the UN to take over peacekeeping and diplomatic efforts are now focusing on a force that includes UN and AU components which is hoped will meet the approval of all sides.
UN spokesman Yves Soroboki told the BBC's Network Africa that the meeting was convened to "hopefully bring about an agreement, first on a transition to a hybrid force which would be of course primarily made up and led by the African Union, but with a substantial contribution of UN military police advisors, and advisors in other areas as well".
Armed men on horses and camels killed those they found in Sirba, say UN and AU officials.
"The attackers were on camels and horses. Reports indicate up to 30 villagers killed and 40 injured and half of the village was razed," an AU official told the Reuters news agency.
A rebel official said the Sudanese army had taken part in the attack, 45km (30 miles) north of the West Darfur capital, El-Geneina.
The government has repeatedly denied charges that its army has worked with the Janjaweed militias to drive black Africans out of Darfur.
Some aid workers have left the region, saying it is too dangerous.
The UN Security Council has passed a resolution for 20,000 troops to be sent to Darfur but Sudan has refused to let the UN take control, saying that would infringe its sovereignty.
UN assistant secretary-general for peacekeeping operations Hedi Annabi said the extra money would be for extra equipment for the AU force.
French Foreign Minister Philippe Douste-Blazy travelled to Darfur on Monday and told local officials the international community had no "hidden agenda" for Darfur.
"There is only the will to no longer see thousands of people in war," he said.
Some 200,000 people have died in Darfur and two million made homeless, with pro-government militias accused of genocide against black Africans.
Sudan's government says the scale of the problems in Darfur are being exaggerated for political reasons.
Neighbouring Chad has declared a state of emergency after the violence in Darfur spilled over the border.