South Sudan is sliding back into civil war. The violence spreading in Jonglei and elsewhere represents the fallout from President Salva Kiir’s decision to abandon the 2018 peace agreement that brought an end to the last civil war, dismantle the unity government and shift to a military strategy for defeating his political opponents. In March 2025, Kiir, an ethnic Dinka, placed First Vice President Riek Machar, a Nuer, under house arrest and subsequently charged him with treason. Kiir’s move was part of a shakeup of his regime that appears connected to his ailing health and intense jockeying among top regime figures to be in a place to succeed him as president. Yet by arresting Machar and shelving the 2018 accord, Kiir sparked a renewed insurgency. As the country’s turmoil deepens, the risks are growing that the South Sudanese conflict will gradually overlap with the one in Sudan, with the two feeding off each other. 

The stakes in South Sudan, whether in terms of humanitarian effects within the country or reverberations in nearby states, are strong reasons for the EU and its member states to keep the spotlight on South Sudan and continue assisting its people. The stability not just of South Sudan but of a large part of East Africa and the Horn of Africa – a region the EU declared as strategically important – is under threat from existing wars and the threat of fighting between Ethiopia and Eritrea. The EU has provided comprehensive support to South Sudan since its independence in 2011, and the bloc as well as some of its member states now stand out as major humanitarian donors to the country. While the main leverage over the conflict parties remains in the hands of regional powers, the EU should exploit its clout as a vital donor to support African mediation efforts and help find a way forward for South Sudan.

South Sudan’s return to warfare in early 2026 marked the failure of over a decade of efforts to extract the country from its previous conflict and ensure that it would not recur. Post-independence power struggles between President Kiir and former Vice President Machar gave rise to a devastating civil war from 2013 to 2018. The fighting shattered the ruling party, displaced nearly half the population and drew in Uganda (backing Kiir) and Sudan (favouring Machar). The 2018 agreement that restored Machar to the vice presidency was a tactical compromise, brought upon Kiir by pressure from Uganda and Sudan rather than any genuine spirit of reconciliation. Not long thereafter, the 2019 ouster of Sudan’s Omar al-Bashir caused the regional balance of power to collapse, allowing Kiir and Uganda’s President Yoweri Museveni to isolate Machar. Confined to the capital Juba from 2020 to 2025, Machar put up no armed resistance, but deep grievances festered among the ranks of his supporters, as the government failed to integrate the opposition forces into the national army or adopt a permanent constitution, both core elements of the 2018 peace deal.

The country’s political order has nevertheless proven brittle. Stability hinges on petrodollars, which help maintain a transactional power sharing compromise among factious elites. In February 2024, the Petrodar pipeline in Sudan ruptured, in effect severing South Sudan’s economic lifeline and slashing state revenue by 70 per cent. This catastrophic loss of revenue persisted for more than a year, gravely weakening the Juba regime, before the pipeline was repaired. Deprived of funds, President Kiir seemed to abandon his “big tent” policy of co-optation in favour of a crackdown on other powerful regime figures. He retreated into a dynastic strategy, relying almost exclusively on immediate family and ethnic kin to keep control.

Kiir moved first against his top security official. In October 2024, he dismissed long-serving intelligence chief General Akol Koor Kuc, breaking up the sprawling intelligence system that had protected him for a decade and leaving him militarily vulnerable. He then deposed his long-time vice president and ruling party deputy chair, James Wani Igga, and elevated business partner and political neophyte Benjamin Bol Mel to those positions, before casting Bol Mel aside in November 2025 and reappointing Wani Igga. As his circle of trust shrank, Kiir concentrated power within his family, appointing his daughter, Adut, as a senior presidential envoy in August 2025. These changes and other purges alienated several veteran party and military loyalists. 

Amid all these reshuffles, Kiir also moved against Machar. In March 2025, Kiir placed Machar under house arrest and charged him with treason. The decision backfired. Though Machar’s political movement has been languishing, his core supporters were galvanised by what they perceived to be a show trial of their leader, while his military forces forged renewed bonds with communal militias as they sought to rekindle their insurgency against Kiir’s government. 

Violence began in the form of local skirmishes in Jonglei on 24 December 2025, but soon took the shape of an organised campaign orchestrated by Machar’s party and the allied White Army, a predominantly Nuer youth militia. Over several weeks, the opposition captured three towns in northern Jonglei. Fearing that the opposition would take the state capital, Bor, the government launched a major counteroffensive in mid-January. They mobilised the national army alongside a coalition of ethnic militias, including the Agwelek under General Johnson Olony. Senior commanders have also resorted to alarmingly inflammatory rhetoric, much of it exploiting ethno-political grievances. In recorded remarks, Olony ordered his advancing forces to “spare no lives”, not even those of the elderly. He also told his troops to ransack houses and slaughter chickens. 

At the same time, both sides are now far weaker than they were at the height of the first civil war (2013-2018), which was characterised at its peaks by large-scale ethnic warfare. Following that period, the country endured years of protracted turmoil (2018-2025), marked by sub-national, inter-communal violence, splinter group insurgencies and severe economic decline. This prolonged crisis has depleted state coffers; irregular pay has in turn led to widespread troop desertions and eroded morale, leaving the national army overstretched. Government forces and proxy militias like the Agwelek are increasingly forced to live off the land. Government offensives thus often appear driven as much by the need for plunder and taxes as by purely military objectives.

On the other side, opposition forces have lost vital supply lines from abroad and are also beset by internal fissures. Machar’s detention set off tussles between his wife, Angelina Teny, and the deputy chairman of his party, Oyet Nathaniel, who is also officially acting as party leader while Machar is in custody. Machar’s new rebel army is also heavily reliant on the rapid mobilisation of local communal militias, which could easily peter out. The youth militias are driven primarily by their own interests, including community defence and the prospect of loot, not by a coherent political strategy.

This mutual degradation could result in a protracted conflict that resembles the low-intensity fighting toward the end of the previous civil war, when the government was unable to quell numerous pockets of insurgency, while the rebels found it impossible to turn the tide against the government. Adding to the government’s vulnerability is the uncertain posture of its traditional guarantor, Uganda. Though President Museveni has already intervened with his country’s military on Kiir’s behalf, it remains unclear how long he will be willing to underwrite Kiir’s survival this time round, especially given South Sudan’s economic collapse and Kampala’s other regional commitments.

The war in neighbouring Sudan adds another layer to tensions in South Sudan. Juba has officially maintained strict neutrality in Sudan’s civil war, which started in 2023. Even so, Juba’s close links to the paramilitary Rapid Support Forces (RSF), which now control much of Sudan’s border with South Sudan, are plain to see. Many in Juba suspect that the Sudanese army, the RSF’s main foe, has reactivated its links to South Sudan’s Nuer opposition forces in a bid to press Kiir to rein in RSF activity, as well as to cut RSF supply lines near the border. Machar’s forces strongly deny getting Sudanese backing and say their forces are forced to scrape by with what they can find locally; indeed, there is no clear evidence that South Sudan’s opposition has received major arms shipments. Still, the Upper Nile region in South Sudan risks becoming a proxy theatre of Sudan’s war should relations between Juba and Khartoum deteriorate further. 

The human cost of South Sudan’s longstanding predicament is staggering. The UN-coordinated South Sudan Humanitarian Needs and Response Plan has sounded the alarm about a dire situation: humanitarian needs are great, while funding has dropped to its lowest level since 2011. The Plan estimates that 10 million people, or more than two thirds of the population, will require humanitarian assistance in 2026. Even so, aid workers are already unable to help nearly as many people as they once did.

The EU is one of the top humanitarian donors in South Sudan, contributing 106 million euros in 2025, down from 110.2 million euros in 2024. But the EU’s support for the destitute comes with a dilemma: it funds basic services in a country where the state has abdicated its responsibility to care for its citizens. Despite generating substantial oil revenues, the government in Juba allocates a negligible fraction of the national budget to health care, education and food security. Instead, state wealth is routinely diverted to the security apparatus and elite patronage networks. Complete European disengagement, on the other hand, would hurt the weakest hardest. If the EU and other European donors were to abruptly withdraw their funding – especially on the heels of severe aid cuts by the United States over the last two years – South Sudan’s political elites might weather the initial shock, albeit at the risk of great competition among them. The South Sudanese people, however, would suffer immediately. 

Sheer humanitarian need has been and should be enough to prompt an EU response. But as the conflict deepens and spreads, the case for the bloc to step up its engagement is strengthening. With the 2018 peace process now dead and elections planned for 2026 impossible to hold in any credible way, South Sudan’s instability could add to that of the region. A collapse of basic survival systems in the country could generate mass cross-border displacement. At present, more than 2.4 million South Sudanese are refugees, with some 2.6 million more displaced internally. The fighting in Jonglei has displaced an additional 280,000 people. Unlike in previous crises, these people have nowhere to run – Sudan is at war and Ethiopia is far from stable. When South Sudan’s neighbours last reached their maximum absorption capacity, at the height of the 2013-2018 civil war, secondary displacement drove migration flows northward toward North Africa and across the Mediterranean Sea. 

Yet the renascent conflict in South Sudan is coming at the same time as European powers are scaling down their diplomatic and development commitments to the country. By the end of 2026, only a slim EU delegation and two EU member states (France and Germany) will maintain a diplomatic presence in Juba. South Sudan is not a priority file, with an EU official calling it the “most forgotten of forgotten crises”. Given the rapidly evolving crisis in South Sudan, the EU should seek to reverse this trend. As an immediate first step, the EU should shift its posture away from state building – which is routinely exploited by predatory elites – toward a strategy of containing local conflict and preventing wider collapse, leveraging its remaining influence to protect civilians and halt regional spillover.

The EU and its member states should: 

• Strategically leverage their humanitarian footprint. Rather than resorting to sanctions regimes, which are easily evaded, as the main ballast for its political engagement in South Sudan, the EU should use its position as a primary donor to press hard for protected access corridors, particularly in opposition-held areas of Jonglei and Upper Nile. The EU should also ensure that its remaining humanitarian assistance is accompanied by diplomacy to compel warring factions to respect international humanitarian law and protections for civilians. 
• Press for de-escalation and coordinate regional leverage. The EU – alongside key regional powers – should keep pushing for Machar’s release and new ceasefire discussions. The bloc should work directly with South Africa (which chairs the African Union’s High-Level ad hoc Committee for South Sudan, or C5, and is a close ally of Juba) and Kenya (which has launched a mediation effort called Tumaini intended to bring holdout groups into the peace process) to seek a de-escalation of the conflict in South Sudan. Together, they should push Uganda, Kiir’s closest ally, to work with them to stabilise the country, starting with dialogue between Kiir and Machar aimed at reducing violence. Concurrently, the EU member states on the UN Security Council should work to empower the UN Mission in South Sudan.
• Withhold support for the scheduled December elections. Conducting elections in the current climate of violence and political fracture is unsafe and could deepen the country’s unrest. The prerequisites for a credible or responsible vote do not exist, and the EU should not be associated with or confer any legitimacy plans to proceed with balloting. The EU should push for peace, political reconciliation and dialogue as prerequisites for scheduling future polls. 
• Focus on circumscribed, ground-level peacebuilding. With formal, top-down transitional justice practically impossible now that the 2018 peace agreement has broken down, the EU should direct its limited resources toward bottom-up, community-level reconciliation dialogues aimed at breaking cycles of inter-communal revenge. Additionally, the EU should build the capacity of local civil society to securely document human rights abuses to hold perpetrators accountable in the future. Furthermore, while being careful not to duplicate existing efforts, the EU should fund and facilitate Track II diplomacy – unofficial dialogues involving civil society leaders, academics and local elders – in close coordination with humanitarian organisations that have access to field commanders and a strong grasp of local conflict dynamics. Women-led organisations, many of which are already leading these informal processes, should be key partners for both dialogue and human rights monitoring efforts. 
• Coordinate more within Team Europe. Given that the EU and its member states have a small diplomatic footprint in South Sudan, the EU should consider boosting coordination with the UK (which was the most active EU member state on South Sudan prior to leaving the bloc), Norway and Switzerland. This coordination could include diplomacy and intelligence. With the U.S. stepping back from its traditional leadership role in Juba, European countries still active in South Sudan should seek to coordinate more effectively to maximise their collective influence.