A senior United States diplomat has issued a stark warning to South Sudan’s leaders, urging them to fully implement the country’s fragile 2018 peace agreement amid escalating violence and mounting fears of a return to all-out war.

Speaking in Juba, the head of the US State Department’s Bureau of African Affairs, Nick Checker, called on the transitional government to “take urgent action to restore peace” and to treat the 2018 accord as the cornerstone of the country’s political future.

In a statement released by the US embassy, Washington pressed South Sudan’s authorities to move beyond rhetoric and demonstrate concrete progress on key provisions of the deal, including security arrangements, constitutional reforms and preparations for long-delayed national elections.

Checker acknowledged that the peace agreement is “flawed” but insisted it “provides the basis of legitimacy for the transitional government,” warning that any attempt to sideline or selectively apply it would deepen instability and undermine international support.

The US also sharply criticized the detention of First Vice President Riek Machar, the main rival to President Salva Kiir and leader of the Sudan People’s Liberation Movement-in-Opposition. Machar, a central signatory to the 2018 accord, was arrested, suspended from office and charged with treason, murder and crimes against humanity.

“It is farcical to claim that inter-party dialogue is taking place while Machar is on trial,” Checker said, arguing that credible political negotiations cannot occur when a principal opposition leader is behind bars.

The US official further accused South Sudan’s leadership of exploiting overlapping crises to attract foreign aid while failing to channel state revenues, particularly from oil, into basic services for citizens and “obstructing the delivery of lifesaving assistance.”

Armed clashes between government forces and opposition elements continue in several regions, displacing tens of thousands of people. Aid agencies report frequent attacks on staff and convoys, severely hampering relief operations.

Despite years of international assistance and substantial oil income, humanitarian indicators are worsening. Nearly two-thirds of the population, about 7.9 million people, are facing severe hunger, according to a joint assessment by the government, the United Nations and humanitarian organizations.

South Sudan is scheduled to hold its first national elections since independence in December, after repeated delays. Diplomats and analysts warn that unless the 2018 peace deal is fully honored and political space is opened, the polls could become a flashpoint rather than a milestone toward stability.