* Deal would sideline ICC-wanted rebel commander
* Uganda, mediator in conflict, not yet behind deal -source
By Jonny Hogg and Elias Biryabarema
KINSHASA/KAMPALA, March 7 (Reuters) - Democratic Republic of Congo is close to securing a peace deal with one of two factions of the M23 rebels who seized swathes of the country's mineral-rich east during a year-long revolt, security sources said on Thursday.
The sources, who spoke on condition of anonymity, said Kinshasa has offered to integrate fighters loyal to Sultani Makenga into the army in a deal that would isolate rival rebel leader Bosco Ntaganda.
Ntaganda, a renegade Congolese army general, is wanted by the International Criminal Court for alleged war-crimes.
Reports of the deal, promoted by Congolese President Joseph Kabila, came after peace talks hosted by Ugandan President Yoweri Museveni in Kampala stalled. Clashes broke out between the two rival M23 factions late last month.
"Kabila was here last week to inform Museveni that he has a deal with Makenga," a senior Ugandan security source told Reuters in Kampala. "(Kabila) thinks once he strikes a deal with Makenga, then Ntaganda will be too vulnerable and isolated to continue fighting."
The source said that Museveni had not yet backed the plan as he was worried about sidelining Ntaganda's faction.
Previous deals to end decades of instability in Congo's mineral-rich east have failed.
Neither rebel faction nor Kabila's office would comment on the reports. A spokesman for Congo's government said he was not aware of any such talks.
However, a senior Congolese army officer said he was preparing for the re-integration of M23 fighters into the army's ranks in anticipation of the deal being swiftly concluded.
"I think the deal is already done, negotiated by the presidency," the officer said.
The M23 rebel campaign is the latest in a series of rebellions led by ethnic Tutsis arms against Congo's army a decade after the official end of a 1998-2003 war, which has been blamed for the deaths of some five million people.
Late last year, the rebels seized Goma, the main town in North Kivu province and home to around 1 million people, in a major embarrassment for the army and U.N. peacekeepers supporting them.
U.N. experts accused neighbouring Rwanda of backing the rebels. Kigali denied the charges but has seen hundreds of millions of dollars in aid slashed by donors as a result.
Ntaganda was a senior figure in the last rebellion, which was officially declared over in 2009 when Kinshasa and Rwanda used Ntaganda to sideline then-leader Laurent Nkunda.
This time around, Ntaganda's faction has repeatedly accused Makenga of striking a deal with Kinshasa, and they have vowed to defend themselves against any attack on their positions in the forests north of Goma.
The M23 has named its former spokesman and Makenga-loyalist Bertrand Bisimwa as the new political head of the movement after Jean-Marie Runiga was sacked late last month for backing Ntaganda.
Ntaganda is wanted by The Hague-based International Criminal Court on charges of killing civilians during a previous uprising. (Editing by David Lewis and Jon Hemming)