KHARTOUM, Jan 15 (Reuters) - A proposed ceasefire between Darfur rebels and the Sudanese government has exposed cracks in the fragile military alliance between insurgents in Sudan's west, highlighting the long road ahead for peace talks.
The ceasefire was negotiated by U.S. governor of New Mexico Bill Richardson in a visit last week and the 60-day truce was to begin on a date fixed by the African Union and the United Nations who are mediating peace efforts.
Richardson said he had met Darfur rebel leaders who had agreed to the ceasefire, but that backing is not unanimous.
Many Darfur rebel commanders who rejected a May peace deal with the government formed a new alliance called the National Redemption Front (NRF) and renewed hostilities with the government in June.
On Monday Jar el-Neby, a commander from a faction of the NRF called the G-19, said he would abide by the truce.
"We do agree with the truce," he said. "Others in the NRF say they don't agree, but we do agree to it."
But leaders from another NRF faction, the Justice and Equality Movement (JEM), said there was no ceasefire.
"This declaration of ceasefire is unilateral by the government. There is no coordination with JEM at all," JEM leader Khalil Ibrahim told Reuters from Darfur on Monday.
Other commanders from the NRF also said they would not abide by the truce.
The divisions show the fragile NRF alliance is a military convenience, analysts said. Politically the groups have very different views, a major obstacle to the previous peace talks and one likely to dog any new negotiations.
Rape, pillage and murder has killed an estimated 200,000 and driven around 2.5 million from their homes in four years of violence called genocide by Washington. Khartoum denies genocide.
Ibrahim said he wanted a political agreement first, saying a ceasefire had strengthened the government's position in previous rounds of talks which led to the unpopular May deal, signed by only one of three negotiating rebel factions.
Since then, the rebel factions have splintered into more than a dozen groups.
A U.N. bulletin said up to 51 people had been killed in different inter-tribal clashes in South Darfur in the past week. The clashes between various tribes have continued since the new year and the government has been unable to stem the fighting.
"Several villages were attacked and buurned... and a large number of villagers have been displaced," the U.N. bulletin, sent late on Sunday, said.