General Oyai Deng Ajak, former chief of staff of the SPLA, said the revitalized peace deal must be renegotiated if durable peace is to be achieved.
General Oyai is a leading of the R-SPLM, a newly formed political movement led by the former secretary general of the ruling SPLM Party, Pagan Amum.
Several armed groups, including the National Salvation Front (NAS) led by General Thomas Cirillo and South Sudan United Front (SSUF) led by General Paul Malong are not part of the peace deal.
Speaking to Radio Tamazuj on Thursday, General Oyai, who held other positions after leaving the military, including becoming the minister of investment and national security, said any discussion on peace with the holdout opposition groups should include the reopening of the 2018 peace agreement.
He, however, pointed out that if President Salva Kiir refuses to reopen the revitalized peace deal, then he must implement it in good faith to enable their return to work as opposition parties in Juba.
“If Salva Kiir does not want to implement the agreement, we have an alternative plan to access Juba,” Oyai said.
The opposition official, who lives in exile, accused President Kiir of ignoring the basic issues like the security arrangements and boundaries, while insisting on forming a Transitional Government of National Unity in November.
General Oyai's comments came in response to recent calls by President Salva Kiir and the leader of the SPLM-IO, Riek Machar to the holdout opposition groups to join the revitalized peace agreement.
South Sudan’s President Salva Kiir and opposition leader Riek Machar agreed earlier this month to form a transitional government by November 12.
The 2018 peace agreement, which called for a unity government, has been delayed due to lack of money to fund the integration of all the armed groups.