ABU DHABI, Nov 25, 2025 (BSS/AFP) - Sudan's army said Tuesday it repelled a paramilitary assault on a key southern city, as Washington urged both sides to accept a ceasefire proposal aimed at stemming one of the world's worst humanitarian crises.

Since April 2023, the army and the paramilitary Rapid Support Forces have been locked in a brutal conflict that has killed tens of thousands of people and displaced nearly 12 million.

Speaking in Abu Dhabi on Tuesday, US Africa envoy Massad Boulos said neither of Sudan's warring parties have accepted a new truce proposal from the Quad group that includes the United States, Saudi Arabia, the United Arab Emirates and Egypt.

"We appeal to both sides to accept the humanitarian truce as presented without preconditions," the US envoy said.

His remarks came hours after RSF commander Mohamed Hamdan Daglo declared a unilateral three-month truce, before the army reported his fighters subsequently attacking a key base in the country's south.

Recent days have seen renewed diplomatic activity after US President Donald Trump said last week he would move to help end the war, following discussions with Saudi Crown Prince Mohammed bin Salman during a visit to Washington.

- Fighting persists -

The Sudanese army on Tuesday said it repelled an RSF assault on its infantry base in the strategic West Kordofan town of Babanusa, its last major stronghold in the region.

Babanusa lies on a vital transport corridor linking the capital Khartoum through the Kordofan region to Darfur, where the army last month lost El-Fasher -- its last stronghold in the western region.

Over two years of conflict, both sides have repeatedly violated every ceasefire agreement. Diplomatic efforts to halt the fighting have failed to make any breakthrough.

A US-backed plan put forward on behalf of the Quad in September called for a three-month humanitarian truce, followed by a permanent ceasefire and a nine-month transition to civilian-led governance.

The army rejected the proposal, which also hinted at excluding both the army and the RSF from Sudan's post-war political roadmap.

Burhan this week said he had dismissed a plan put forth by Boulos this month as "the worst yet", accusing him of parroting the UAE's talking points.

- 'Overlook those comments' -

Boulos on Tuesday spoke alongside UAE presidential adviser Anwar Gargash, whose country has repeatedly denied widespread reports that it arms the RSF.

Boulos rejected Burhan's accusations of bias.

"He was making reference to something that does not exist, that has never been presented by us. So we have no idea what he is talking about," the US envoy said.

"We have to overlook those comments and remarks and focus on the heart of the matter which is the humanitarian crisis," he added.

In recent weeks, reports of atrocities in Sudan have shocked the world after the RSF seized El-Fasher at the end of October.

Earlier Tuesday, rights group Amnesty International accused the RSF of committing war crimes in El-Fasher, and said the UAE had "facilitated" their operations.