S.Sudan general, oil minister arrested in threat to peace deal

South Sudan, the world's youngest country, ended a five-year civil war in 2018 with a power-sharing agreement between bitter rivals, President Salva Kiir and his deputy, Machar.

But growing unrest in Upper Nile state in the country's northeast has threatened to undo their unity government, with the army accusing Machar's allies of supporting rebels in the region.

General Gabriel Duop Lam, a close ally of Machar, was arrested on Tuesday, according to a statement from Machar's spokesman.

Machar's residence in the capital Juba was also surrounded by troops of the South Sudan People's Defence Forces (SSPDF), the regular army allied to Kiir, according to the statement.

Petroleum Minister Puot Kang Chol, another Machar ally, was arrested overnight.

"Puot Kang Chol, several family members, and his bodyguards were arrested at his residence in Juba. The operation was conducted by personnel identified as members of the National Security Service," his press secretary wrote in a statement on Facebook.

The civil war between Kiir and Machar began in 2013 just two years after the country gained independence from Sudan, and left some 400,000 people dead.

Many steps of the peace agreement have remained unfulfilled, including writing a constitution, holding elections and unifying their armed forces -- while the country remains mired in poverty despite significant oil deposits.

- 'Gravely concerned' -

Machar's spokesperson Pal Mai Deng said in a statement that the general's arrest on Tuesday "violates" the peace deal and called for an intervention by international partners.

"This act puts the entire agreement at risk," he said.

"We take this opportunity to call upon the guarantors of the Agreement and partners to intervene in order to avoid a return to full-scale violence."

The immediate trigger has been the mounting unrest in Upper Nile state.

The SSPDF has accused Duop Lam and his troops of working with the so-called White Army rebels in the region, who are predominantly from the same ethnic Nuer community as the general.

The UN Mission in South Sudan last month reported increased fighting between the army and "armed youth" in Nassir county in Upper Nile, involving "heavy weaponry which has, reportedly, resulted in deaths and injuries to civilians as well as armed personnel".

On Wednesday, the Intergovernmental Authority on Development, a bloc of eight regional countries, expressed "deep concern" about the violence.

The armed clashes "threaten to undermine the hard-won gains achieved in the (peace agreement) and exacerbate the already dire humanitarian situation in the region," the bloc said in a statement.

Kiir held a meeting of ministers, including Machar and the petroleum minister, on Monday to discuss the unrest, and the deployment of fresh SSPDF forces to the region.

It is not the first time the president has been accused of undermining the peace deal.

He fired two of the five vice-presidents in his unity government without consulting other stakeholders last month, which Machar said threatened "the very existence of the Agreement".

Elections that were due to take place in December were postponed for two years, having already been delayed from 2022.