U.N. Secretary-General Kofi Annan has called on the Security Council to issue its "strongest warning" to forces fighting in Sudan to sign a peace deal before the end of the year.
"I regret to report that the security situation ... continued to deteriorate despite the cease-fire agreement signed earlier," Annan told Security Council members, who were holding a rare meeting outside their New York home.
"Both the government and its militias as well as the rebel groups have breached these agreements," The Associated Press quoted Annan as saying Thursday. "The strongest warning to all the parties that are causing this suffering is essential."
"When crimes on such a scale are being committed, and a sovereign state appears unable or unwilling to protect its own citizens, a grave responsibility falls on the international community, and specifically on this council," he said.
The 15-member council is meeting in the Kenyan capital of Nairobi to find an end to a 21-year civil war in Sudan's south and a humanitarian crisis in the western Sudan region of Darfur.
Nearly 2 million people have died, largely through war-induced hunger and disease, in a conflict between Sudan's Arab north and its Christian and traditionalist south.
The Darfur crisis began in February 2003, when non-Arab rebel groups took up arms to fight for more power and resources. The government responded by backing Arab militias, who have driven millions of villagers from their homes.
The United Nations has called Darfur one of the world's worst humanitarian disasters, and Washington has labeled it genocide.
Twenty-one months of violence have left tens of thousands dead and driven 1.8 million people from their homes, international officials say. Some 200,000 of the refugees have fled to neighboring Chad.
Sudanese Vice President Ali Osman Taha told the Security Council his country was committed to peace.
AP quoted Taha as saying "the war in Darfur ... has been instigated by local parties who receive support from foreign parties." He did not elaborate.
Also, in a rare address to the council by a rebel leader, John Garang told members that only four issues remain to be resolved before a comprehensive agreement ending the southern war can be signed, AP reported.
The government and Garang's rebels, the southern Sudan People's Liberation Army, said they would reach a final deal by December 31.
U.S. ambassador to the United Nations John Danforth, who called the Security Council meeting, welcomed the announcement as a major step forward.
"The peace agreement is going to be signed by December 31," Danforth told reporters. "The parties will sign a memorandum of understanding that will commit them to signing the peace agreement by the end of the year."
A peace deal has been on the books since earlier this year, calling for north-south power sharing and a new constitution, but it remains only a paper peace.
Garang said ending the southern war will help keep chaos from engulfing Sudan, which is plagued by a number of small but growing insurgencies.
"The situation in Darfur is rapidly degenerating into chaos and anarchy as the government's counterinsurgency policy ... has seriously boomeranged," Garang said.
The council is expected to adopt a resolution on Sudan Friday.
The council's draft resolution is holding out a carrot of development aid, including debt relief for all parties, once a north-south pact is sealed. But so far there is no sign of a stick other than U.S. sanctions.
There are divisions on the 15-member council. Russia, China, Pakistan and Algeria object to strong language in a draft declaration condemning the atrocities in Darfur.
Earlier, the four abstained on a council resolution threatening an oil embargo if the Sudanese government failed to rein in the militias and hold them accountable for human rights atrocities.
In September, U.S. Secretary of State Colin Powell -- who has called the violence in Darfur a genocide -- accused the four countries of valuing business with Sudan over humanitarian concerns.
Ahead of Thursday's meeting, human rights groups insisted the council take a harder line by imposing an arms embargo or threatening sanctions against the government.
"Unless they are held accountable for abuses in the south, the Sudanese authorities will continue to believe they can get away with murder in Darfur," Jemera Rone of New York-based group Human Rights Watch said.
"We very much want a peace agreement for the south because they've been at war for 21 years now and that's enough."
The Security Council meeting is the first away from New York in 14 years, and only the fourth outside the United States since the United Nations was founded in 1945.