JUBA, Dec. 14 (Xinhua) -- The UN refugee agency on Friday appealed to South Sudan's warring parties to the conflict to maintain peace to help end five years of displacement.

Filippo Grandi, UN High Commissioner for Refugees reiterated his appeal to all parties to continue pursuing a sustainable and lasting peace to help heal wounds of conflict.

"The people of South Sudan, many of whom have been displaced multiple times in their lives, deserve an end to their suffering," Grandi said in a statement on the eve of the fifth anniversary of the start of conflict in South Sudan.

"Peace must prevail. The wounds of this conflict will take time to heal, but that process can only be sustained through warring parties engaging in dialogue, finding political solutions and laying down their arms once and for all," he added.

The world's youngest nation has remained mired in instability and conflict, which has displaced an estimated four million people, both internally and externally, according to the UN.

"UNHCR stands ready to assist efforts to achieve a genuine and inclusive peace process, including supporting the meaningful and inclusive participation of refugees in any agreement," Grandi said.

President Salva Kiir and rebel leader Riek Machar signed a new peace deal in September amid high hopes that this will finally end the years of brutal conflict.