The absence of South Sudan's rebel leader Riek Machar should not delay the implementation of a peace deal, an envoy to the UN Security Council said on Monday.
Former vice president and rebel leader Machar is undergoing medical treatment in Khartoum after being chased from South Sudan's capital in July by forces loyal to President Salva Kiir. Machar has since been replaced by former ally Taban Deng Gai.
"Taban Deng is serving as vice president and he will stay in that position until the return, if there is a return, of Riek Machar," Alexis Lamek, France's deputy UN ambassador told AFP after meeting the African Union's Peace and Security Council in the Ethiopian capital Addis Ababa.
"For us, what is certain is that this issue should not delay implementation of the peace agreement. It is necessary to move forward," he said.
The Security Council was in Addis Ababa at the end of a four-day visit to the region to push for peace in South Sudan, the world's youngest nation which has been wracked by war since 2013.
Machar's appointment as vice president was a key provision of a year-old peace deal that has so far failed to end the fighting in South Sudan which began with a dispute between Kiir and Machar in December 2013.
Since Machar's flight from Juba he has been sidelined domestically and internationally.
Last month, US Secretary of State John Kerry signalled Machar's waning importance saying, "there is an allowance for the replacement of personnel and that has been effected with the appointment of a new vice president."
In Addis Ababa, UN and African diplomats also discussed a proposed 4,000-strong UN protection force for South Sudan.
Which countries will contribute troops, when they will arrive and what their mandate will be are still under discussion despite South Sudan agreeing in principle to the deployment at the weekend.
Lamek, who spent three days in South Sudan prior to arriving in Ethiopia, said the protection force is necessary because the situation in South Sudan is "more alarming that we imagined".
Aside from the tens of thousands of people killed, the United Nations has reported shocking levels of brutality including gang-rapes and the wholesale burning of villages.
An estimated 16,000 children have been recruited by armed groups and the national army in the conflict, and 2.5 million people have been driven from their homes.