The next round of the South Sudan peace talks has been adjourned to next month, the monitoring agency said.
The talks in Addis Ababa were scheduled to begin on April 26 to April 30.
However, the regional bloc's Joint Monitoring and Evaluation Commission (JMEC) said there was a need for more time for consultations among the parties involved.
A delegation of JMEC has been in Juba since last Saturday, meeting with the parties to the conflict and other stakeholders.
South Sudan has been in internal war since December 2013 when President Salva Kiir had a fallout with his deputy Riek Machar.
Attempts to put off the conflict have been futile as multiple truces have been violated by the main signatories to the peace.
The UN warned that the over three million South Sudanese would become refugees this year, thanks to the conflict.