"The Arusha intra-party agreement did not undo the Intergovernmental Authority on Development (IGAD) peace process," presidential spokesperson Ateny Wek Ateny told The Anadolu Agency on Sunday.
"The IGAD peace process is the one that will lead to a comprehensive peace agreement being signed," he insisted.
South Sudanese President Salva Kiir and his sacked vice-president, Riek Machar, signed a deal on Wednesday to reconcile their rival factions of the SPLM in a step towards resolving the country's ongoing political crisis.
The signing ceremony was presided over by Tanzanian President Jakaya Kikwete and attended by Kenyan President Uhuru Kenyatta and his Ugandan counterpart, Yoweri Museni.
South Sudan, which became independent in 2011, has been shaken by violence since late 2013, when Kiir accused Machar of leading a failed coup attempt against his regime.
Hundreds of thousands of South Sudanese have since been displaced in fighting between the two rivals, close to two million have been uprooted from their homes, and hundreds of thousands now seek shelter in refugee camps across the country.
In recent months, the warring camps have held on-again, off-again peace talks in Addis Ababa, Ethiopia under the auspices of IGAD, a regional bloc based in Djibouti.
A fresh round of talks is expected to be held this week in the Ethiopian capital.
"Our team is going to negotiate the grand peace," Ateny told AA, adding that a government negotiating team had left for Addis Ababa on Sunday and that talks would begin on Tuesday.
Ateny said President Kiir had, again, stressed to his negotiating team the need for negotiations to be conducted in good faith.
"The president always tells them to negotiate in good faith, simply because peace is crucial for the country; whatever the government gives in [i.e. concedes], it is on the basis of bringing peace to South Sudan," Ateny told AA.
"So all the concessions that are given by the government are on the basis of bringing peace," he said. "The president is continuing to urge the government negotiating team to be vigilant and make sure that they come back with peace."
Ateny said 75 percent of the issues had already been agreed upon at the party's recent reconciliation talks.
"It will make the issues being negotiated [in Addis Ababa] arrived at simply because the majority of those issues were actually included in the Arusha agreement," he told AA.
"Those items addressed in Arusha cannot remain a sticking point, because if you signed in Arusha, there will be no need for you to refuse signing the next one in Addis Ababa," he added.
"Anything agreed upon in Arusha shouldn't come again because now we have the agreement of the unification of the SPLM, and it cannot be reviewed," Ateny said.
"It should now be a subject of implementation," he stressed. "The whole issue is considered done."
Under the Arusha agreement, the two rival SPLM factions agreed on leadership, organizational and political issues, and accountability.
Ateny said that what remained to be discussed in Addis Ababa were the contentious issues of power sharing and command of the military.
"They have to resolve the issue of the executive prime minister or non-executive prime minister, the issue of those who want to maintain their own army, and reforms in all sectors of government," he told AA.
"The government wants only one army because the situation of having two armies is well known, but the rebels are still insisting on a separate army," said Ateny.
He said the government had resolved to sign any agreement reached as soon as possible for the sake of peace.
"The stand of the government is that it will implement whatever has been signed. If the rebels are not willing to sign, the government is ready because… the government doesn't benefit in any way from a state of war," Ateny contended.
"So the government is willing to ensure that peace is reached and people are allowed to choose their representatives instead of some people trying to take power by force," he said.
The spokesperson went on to tell AA that, following the SPLM reconciliation agreement, former detainees were now free to return to South Sudan.
"According to the agreement, they are actually now supposed to come back," said Ateny.
"Former political detainees are supposed to come out and it is only the IO (rebels or SPLM "in opposition") who are taking up arms who should wait for the signing of the Addis Ababa peace talks," he explained.
The spokesperson also said that the government intended to carry on with elections to avoid a potential power vacuum – regardless of whether or not peace was reached.
"The government is still keen to carry on with elections. If the comprehensive peace agreement is signed quickly, there will still be enough time to conduct elections so it doesn't allow a political vacuum," he told AA.
"If peace is not signed," he added, "the elections still must go on."