The Sudanese army has reportedly stepped up military operations against a major Darfur rebel faction which has refused to enter into the current peace talks. Meanwhile, the other main rebel group, which recently signed a ceasefire agreement with the government, is threatening to pull out of talks if Khartoum carries on parallel negotiations with a newly-formed umbrella group of rebel factions.
The Sudan Liberation Movement (SLM) faction still aligned to the founder of the Darfur rebel group, Abdel Wahid al-Nur, has reported days of attacks from the Sudanese armed forces in its stronghold area around the mountainous Jebel Marra area.
The Sudanese army has officially denied the participation in the clashes, which reportedly have been preceded by aerial bombardment on the rebel lines. But the U.S. issued a statement Tuesday condemning the "reports" of violence between Khartoum and the SLM faction, saying that the hostilities are viewed as "undermining the spirit of the peace process."
When contacted on Wednesday by VOA, the spokesperson for the United Nations Office for the Coordination of Humanitarian Affairs in Sudan, Sam Hendricks, said that news from the ground indicates Sudanese forces have been involved in the violence, though he said his office lacked the information to comment any further.
"It's been confirmed in our reports that there were clashes between government forces and rebel groups. And where we don't have reliable information, there is really nothing that we can say at this stage," Hendricks said.
More than 10,000 are thought to be displaced in the weeks of fighting, but the United Nations says the ongoing insecurity is preventing humanitarian aid from reaching much of the affected civilian populations.
Analysts suspect that Khartoum is trying to exert pressure on the rebel group's leader, Abdel Wahid, to enter into peace negotiations. The exiled rebel leader, who is residing in Paris but considered to still maintain significant support on the ground, has repeatedly demanded a cessation of fighting before talks can begin.
When Darfuris took arms in 2003 against the Khartoum regime of Omar Hassan al-Bashir, the movement was comprised of two distinct groups: the Sudan Liberation Movement, led chiefly by Abdel Wahid, and the Justice and Equality Movement group (JEM), led by former government official Khalil Ibrahim.
Last week, Ibrahim's JEM signed a truce with Khartoum which is supposed to lead to a more formal peace deal to be negotiated over the next few weeks. JEM is dominated by the Zaghawan tribe. Chadian President Idriss Deby is also Zaghawan, and Khartoum has long-accused him of providing major support to Ibrahim's rebellion.
Chad and Sudan agreed to end their proxy wars last month, and soon after the cease-fire deal between JEM and Khartoum was hammered out in the Chadian capital.
But analysts say that any lasting peace deal in Darfur will also have to incorporate the main factions of SLM.
SLM's leadership is mostly Fur, the region's most populous people group. Unlike JEM, which is viewed as holding Islamist ideologies similar to those of the Bashir regime, SLM is seeking a more secular form of rule.
Some outside officials have attempted to broaden the Darfuri representation participating in peace talks, which Abdel Wahid continues to snub. U.S. Special Envoy to Sudan Scott Gration helped bring together a group of breakaway SLM officials in Addis Ababa last year, and a separate group of rebel factions also banded together in the Libyan capital.
These two groups have now merged, forming the Liberation and Justice Movement. This new umbrella group apparently hopes to ride the momentum of the JEM-Khartoum deal to strike its own agreement with the government.
But JEM, which has in the past said that it would only accept sharing the negotiating table with Abdel Wahid's SLM faction, is threatening to pull out of the peace framework agreement if Khartoum talks with the new LJM group.
More than 300,000 are thought to have died in the Darfur conflict, although Khartoum rejects these figures.