Fierce battles are raging between Sudan's army and its civil war rival the Rapid Support Forces at several locations in Kordofan, with the paramilitary group believed to be close to seizing a major city in the region's western part.
The RSF has laid siege to Babanusa for more than a year, with troops from the army's 22nd Infantry Division fending off repeated attempts to dislodge them, including a major attack this week.
Unlike Darfur, where ethnic African communities are a significant segment of the population, Kordofan is dominated by nomadic, cattle-herding tribes of Arab heritage whose sons are fighting on the side of the RSF, according to Sami Saeed, a US-based Sudan expert.
"Those tribes make it much easier for the RSF to operate in Kordofan," said Mr Saeed. "For the RSF, controlling Kordofan also gives it valuable leverage with neighbouring South Sudan because it's home to the economically vital pipeline that carries crude oil from South Sudan to export terminals in Port Sudan on the Red Sea."
South Sudan, along with Chad and Libya, is the RSF's vital supply source.
For the army, losing Babanusa would be a serious setback in its 31-month war against the RSF, coming so soon after it was driven out last month from the city of El Fasher, its last foothold in the neighbouring Darfur region.
Like El Fasher, Babanusa has strategic significance, prompting the RSF to bring thousands of fighters from Darfur there to dislodge the army.
It is the nearest major urban centre to Darfur to the west and is on the western end of the road to the capital Khartoum to the east. The city is about 600km south-west of the capital and is close to oilfields near the border with South Sudan.
The RSF ordered residents to leave Babanusa soon after laying siege to the city in early 2024, making it easier for its fighters to enter and surround the garrison, which has received occasional air drops from army aircraft.
The RSF recently shot down an army transport plane that was trying to drop food and ammunition for the troops in Babanusa. The group is trying to dislodge the army from elsewhere in Kordofan that could be used as a launching pad for attacks on Darfur.
Another major flashpoint is the city of Al Obeid, a commercial and aid distribution centre in the north of Kordofan that the RSF has been trying to surround for months.
Intense fighting is also continuing close to Kadugli, an army-held city in the south of Kordofan, close to the Nuba Mountains, where anti-government rebels have been entrenched for years.
"The army will most likely try to hold on to Al Obeid and Babanusa but that will come at a vast cost," said Sudanese military analyst Jaafar Hassa, a retired army brigadier. "The RSF has deployed a large force in Kordofan that's both mobile and fast-moving, and more familiar with the area than the army and its allies."
Analysts say the RSF's campaigns in Darfur and Kordofan have been aided by recently enhanced arms capabilities.
"The Rapid Support Forces' increased arsenal, especially its drones, has become very problematic for the army," said Osman Al Mirghany, a prominent Sudanese analyst and publisher based in Cairo.
Army chief and de facto leader of Sudan, Gen Abdel Fattah Al Burhan, said over the weekend that the armed forces would not negotiate with the RSF and vowed to press on with the war until it is vanquished.
But Mr Al Mirghany and other analysts contend that the two sides are quietly holding indirect negotiations in Washington to hammer out an agreement on a humanitarian truce proposed by the US, Egypt, the UAE and Saudi Arabia as part of a comprehensive peace plan.
Mr Al Mirghany and Mr Saeed believe those negotiations could soon produce an agreement on a three-month humanitarian truce that the four nations hope will be a prelude to a longer ceasefire.
RSF leader Gen Mohamad Dagalo announced last week that he had agreed to the proposed truce, which also provides for a civilian-led government and a return to democratic rule in a process that excludes Islamists loyal to former dictator Omar Al Bashir.
According to Mr Al Mirghany, Gen Al Burhan has set conditions for agreeing to the truce, including the RSF lifting its siege in Babanusa, withdrawing from El Fasher and pulling back from positions close to the army.
Gen Al Burhan and Gen Dagalo are former allies who jointly staged a coup in 2021 that derailed the country's democratic transition and plunged it into political and economic chaos. They later fell out over Gen Al Burhan's insistence that the RSF be assimilated into the armed forces.
Their differences, together with their rivalry to dominate Sudan, boiled over into open warfare in April 2023. More than two and a half years later, Sudan has become the world's biggest humanitarian crisis, with more than half the population of 50 million facing hunger or famine in parts of the vast Afro-Arab nation. And about 14 million people have been displaced.
There are no reliable death tolls for the war, but tens of thousands are believed to have been killed in the conflict, the latest in a series of civil wars that have plagued Sudan since its independence in 1956.
The international community has sanctioned senior Sudanese military and paramilitary officials, accusing them of war crimes, atrocities and actions that have further destabilised the country.
On Tuesday, Sudan's former prime minister Abdalla Hamdok warned in a televised speech that the continuation of this war serves "nothing but destruction. There is no winning side in this catastrophe".
"I make a sincere appeal to the national armed forces and to the Rapid Support Forces: stop this war, stop this bleeding that is consuming the nation. Listen to the cries of the millions who are hungry, sick, displaced, and refugees. Know that inciting the continuation of the fighting is direct participation in the killing.”
Al Shafie Ahmed contributed to this report from Kampala, Uganda
