S. Sudan's Warring Leaders Agree Deadline for Transitional Govt.

South Sudan's president and rebel chief met Tuesday in a bid to end six months of civil war, agreeing to forge a transitional government within a 60-day deadline, Ethiopia's prime minster said.

"They agreed to complete the dialogue process within the coming 60 days on what how, when and who... (for) the formation of the transitional government," Ethiopia's Hailemariam Desalegn said, after the rare meeting between President Salva Kiir and rebel chief Riek Machar alongside regional leaders.

A ceasefire deal signed by Kiir and Machar on May 9 has been repeatedly violated, deepening the crisis in the young nation which has already killed thousands and forced more than 1.3 million people from their homes.

It was the first encounter of the enemies in a month, and only the second since the civil war began in mid-December.

Kiir and Machar met on the sidelines of a regional leaders' summit in Addis Ababa organized by the East African IGAD bloc, which is brokering slow-moving negotiations between both sides.

Hailemariam, speaking at the opening of the summit, slammed both sides in South Sudan for violating a ceasefire agreement signed on May 9.

"There has been a growing tendency to continue with the war," Hailemariam said, but adding both Kiir and Machar had recommitted to the peace deal.

Previous rounds of peace talks have made little progress and been repeatedly delayed.

Delegates for Kiir and Machar have been meeting in luxury hotels in the Ethiopian capital since January, with both sides bickering over the agenda and even the venue of discussions.

Earlier, mediators issued a stinging rebuke of the rivals, accusing them of seeking military victory rather than a negotiated end to the civil war.

Mahboub Maalim, IGAD executive secretary, said both Kiir and Machar were "stupid" if they thought they could win on the battlefield.

"If we want to apportion blame, it's theirs. I think sometimes they thought they could win on the ground militarily, something which is very stupid," Maalim said.