All sides in South Sudan's conflict continue to recruit fighters despite a peace deal signed earlier this year, UN rights investigators said Friday.
"There is a worrying trend, that there is some recruitment going on," said Barney Afako, a member of the UN's Commission on Human Rights in South Sudan.
There has been a let-up in the fighting since a September peace deal, but commission chairperson Yasmin Sooka said the new recruitment "is on all sides" of South Sudan's conflict.
Fighting began five years ago when President Salva Kiir accused his former deputy, Riek Machar, of plotting a coup.
Since then nearly 400,000 people have been killed and millions forced from their homes or to the brink of starvation.
As part of the September pact the warring parties are supposed to stop recruitment -- whether voluntary or forced -- as a permanent ceasefire takes hold.
Afako said the motivation for recruiting new fighters was unclear. He said the move might be "tactical" so that armed groups can argue for a greater share of government demobilisation programmes, or it might be "preparation to return to conflict".
Machar is expected to return to the capital Juba in May, almost three years after he fled in a hail of bullets when a previous peace deal fell apart.
The three members of the UN rights commission were speaking at the end of a four-day visit to the country.