The government responded by mobilising mostly Arab fighters accused of a campaign of rape, murder and looting that created one of the world's worst humanitarian crises. UN officials say that up to 300,000 people have died in the fighting, although the Sudanese government says that number is actually 10,000.
While extending Unamid's mandate until July 31, 2011, the security council called on it to give priority to protection of civilians and ensuring "safe, timely and unhindered humanitarian access" to an estimated two million refugees.
It instructed UN officials in Sudan to develop a "comprehensive strategy" to achieve those targets.
Al Jazeera's Mohammed Adow, reporting from northern Darfur, said the UN/AU forces' efforts have been helping to stabilise the region.
"They have quelled a lot of violence in some of the places they've been deployed, but the mission faces big problems in terms of getting access in some areas where the fighting has been taking place in recent months," our correspondent said.
The renewal of Unamid's mandate comes with a rise in violence in Darfur. At least eight people were reported killed and dozens injured this week at fighting in refugee camps.
Unamid reported earlier this month that 221 people had died in tribal fighting and other violence in Darfur in June after nearly 600 deaths in May.
The council resolution called on all parties to the conflict in Darfur to immediately end the violence and commit themselves to a "sustained and permanent ceasefire".
Ban Ki-moon, the UN secretary-general, accused both the Sudanese government and rebel groups in a report this month of restricting access to areas where there had been fighting.
Abdalmahmoud Abdalhaleem, Sudan's UN ambassador, said his government had placed "no restrictions whatsoever" on Unamid. Aid group Oxfam agreed with the security council that Unamid should focus on security and stay out of reconstruction.
El-Fateh Osman, Oxfam's Sudan head, said in a statement: "Mixing the work of blue helmets [peacekeepers] with aid groups will confuse Darfuris."
Separately, Susana Malcorra, a UN under-secretary-general, told reporters that the United Nations was preparing to expand its presence in semi-autonomous southern Sudan to help prepare for next year's referendum on possible secession for the south.
She said UN personnel would also help with training of local security forces and monitoring for the referendum.
Meanwhile aid group Medicins San Frontieres (MSF), or Doctors without Borders, has suspended work in a violent part of South Sudan because of attacks on its staff.
"Unless the situation improves, it is impossible to evacuate those who need hospitalisation or surgery, including women with obstructed labour, children with cerebral malaria or severe anaemia who need blood transfusions"
Gbane Mahama, MSF medical coordinator in the South Sudan
The group in a statement on Saturday said it was "forced to suspend all activities" in Gumuruk in Jonglei state following three separate security incidents, including theft of medical equipment and violent robbery of four staff members while delivering aid.
"Attacks on our staff and clinics prevent us from providing essential medical aid," Rob Mulder, MSF head of mission in the south, said.
"These incidents are totally unacceptable as they stop us from treating patients and put our staff at risk."
Aid agencies have said violence in the region in 2009 have killed some 2,500 people and displaced 350,000 others.
Jonglei was one of the worst affected states by tribal violence last year and a renegade south Sudan army has also clashed with government troops in the state this year.
"Unless the situation improves, it is impossible to evacuate those who need hospitalisation or surgery, including women with obstructed labour, children with cerebral malaria or severe anaemia who need blood transfusions," said Gbane Mahama, MSF medical coordinator in the south.
MSF said 160 malnourished children were being treated in its Gumuruk clinic with 20 severely malnourished children arriving each week.