ADDIS ABABA: Monitors of South Sudan's fragile cease-fire must deploy immediately, top diplomats warned Friday, as regional leaders met to bolster peace efforts for the war-torn young nation.
Clashes continue despite the deal signed last week by government and rebels, brokered by the East African bloc, the Intergovernmental Authority on Development (IGAD).
IGAD teams are meant to ensure the warring sides honour their deal, but many fear the unarmed observers will struggle to monitor loose frontlines between multiple forces in a vast country with few roads.
Leaders of Djibouti, Ethiopia, Kenya, Somalia and Sudan met on the sidelines of the final day of an African Union summit, where the bloodshed in South Sudan has been a key focus.
Ethiopian Prime Minister Hailemariam Desalegn warned on Thursday South Sudan faced "falling into the abyss" without urgent action.
IGAD special envoy Seyoum Mesfin urged leaders to set up cease-fire monitoring teams within 48 hours, and called on rival sides to ensure a "progressive withdrawal" of forces from frontlines.
Both UN special envoy Haile Menkerios and US special envoy Donald Booth said it was "critical" monitoring teams be put swiftly in place to report on any violations, including by foreign forces.
Teams must be "provided with the necessary political and logistical support as well as unfettered access," Haile said.
Thousands are believed to have been killed in the fighting pitting forces loyal to President Salva Kiir against a loose coalition of army defectors and ethnic militia nominally headed by sacked vice president Riek Machar, a seasoned guerrilla fighter.
Both government and rebels accused each other of violating the deal but insist they are committed to ending a bloodshed in which thousands have killed and more than 800,000 forced from their homes.
"Those who might seek to undermine the peace process should know that we are all watching, and that there will be consequences for such would-be spoilers," Booth added.
Uganda, a key IGAD member, sent in troops to back President Salva Kiir days after fighting broke out, while rebels from Sudan's war-torn Darfur region are also reported to have taken part in battles.
Uganda Foreign Minister Sam Kutesa told reporters there were "no plans yet" to withdraw troops.
"We are not advancing ourselves, we have just stopped the rebels from advancing southwards," he said.
South Sudan's Vice President James Wani Igga said that Uganda would not withdraw from the country as it was a "long battle", although said that forces would "progressively" pull back from frontlines.
Rebel spokesman Lul Ruai Koang claimed fresh clashes on Saturday, reports dismissed as false by army spokesman Philip Aguer.
While South Sudan released seven detainees accused of involvement in an alleged failed December 15 coup bid that triggered the bloodshed, it has also vowed to put on trial seven other key leaders -- three who are on the run -- a move likely to threaten peace efforts.
However, Foreign Minister Barnaba Marial Benjamin told AFP on Thursday that there "definitely there will be a pardon... effective when investigations are over."
Kenyan President Uhuru Kenyatta said Friday he continued to "engage with our brother President Salva Kiir on the release of the remaining four."
The fighting has seen waves of brutal revenge attacks, as fighters and ethnic militia use the violence to loot and settle old scores, with the UN and rights workers reporting that horrific atrocities have been committed by both sides.