– ‘Risk of further conflict’ –
His failure to arrive has thrown an August 2015 peace agreement into jeopardy, with US, Britain and Norway warning in a statement late Friday of the risk of “further conflict and suffering.”
International monitors completed verification of the number of weapons carried by the rebels accompanying him, diplomats said Saturday.
There was no immediate response from the government, who previously said they would clear Machar’s plane to fly once the weapons-checking was completed.
Minister of Information Michael Makuei has previously said he expected Machar to arrive on Monday.
There was growing frustration among the rebel troops in Gambella, who have now been there for several days waiting to leave.
Under intense international pressure, the two sides reached agreement on Friday on the number of troops protecting Machar and the exact number of weapons they can carry.
Machar can bring with him 195 men, carrying AK-47 assault rifles as well as 20 machine guns and 20 rocket-propelled grenades.
Machar, a former rebel leader turned deputy president, started a new rebellion after being fired by Kiir in 2013, fighting his way back to office.
A 1,370-strong armed rebel force has already arrived in Juba as part of the peace deal, and government forces say they have implemented their promise to pull all but 3,420 of their troops from the city.
All other soldiers have to remain at least 25 kilometres (15 miles) outside the capital.