Talks aimed at forging a cease-fire between ex-rebels and Khartoum-backed militias in southern Sudan have failed ahead of this week's scheduled formation of a North-South unity government, officials are saying. The collapse of the weekend talks is likely to cast a pall over Saturday's ceremonial installation of a unity government in Khartoum under a January peace deal which will see John Garang, leader of the former rebel Sudan People's Liberation Movement/Army (SPLM/A), sworn in as vice president.But while unable to reach an agreement, Garang and the southern Sudan militia chiefs did agree to continue with talks which are being mediated by retired Kenyan President Daniel arap Moi, the officials said. The weekend meeting in the Kenyan capital had been aimed at convincing the militias to halt attacks, mostly in Sudan's Upper Nile region, and bring them into the peace pact signed between the SPLM/A and Khartoum in January in Nairobi. "The meeting ended well on Sunday, but without key agreements," a senior SPLM/A official said. "The only thing that was agreed was to continue these talks inside Sudan."