Sudan army's months of silence to alleged Emirati support to its rival, the paramilitary Rapid Support Forces, ended last week with the expulsion of 15 United Arab Emirates diplomats by the foreign ministry.
The military's anger over UAE's alleged funneling of weapons to the RSF has finally boiled over, leading to harsh exchanges between Khartoum and Abu Dhabi, Agence France-Presse reports.
The Sudan army and RSF are battling for control of the country since mid-April, resulting in the deaths of more than 12,000 people caught in the crossfire and displacement of millions.
In November, General Yasser al-Atta, second-in-command to army chief Abdel Fattah al-Burhan, openly denounced the UAE, calling it a "state mafia" that had "taken the path of evil" by supporting the RSF and its leader Mohamed Hamdan Daglo.
Atta accused Abu Dhabi of funnelling weapons through Chad, Uganda and the Central African Republic to the RSF with the help of the Wagner Group, the Russian mercenaries who once enjoyed a foothold in Bangui.
UAE officials did not respond to AFP's request for comment.
Experts have warned of the existence of such a supply line since the start of the war, but until November Sudan's army had not made the accusation publicly.
"Until recently, the Burhan camp exercised caution and diplomacy, avoiding direct verbal confrontations against key players such as Libya's Haftar, Russia and Abu Dhabi," Jalel Harchaoui, associate fellow at the Royal United Services Institute, told AFP.
In August, the Wall Street Journal said aid shipments sent via Uganda and intended for Sudanese refugees in Chad had been found to contain weapons destined for the RSF.
The UAE promptly denied the report. It said Abu Dhabi "does not take sides in the current conflict."
Alex de Waal, an expert on Sudan, said that UAE president Mohamed bin Zayed was a supporter of RSF chief Daglo.
De Waal said the pair forged a relationship in 2015 when Daglo provided paramilitaries for the Saudi-Emirati ground intervention in Yemen's civil war.
Daglo — who controls much of Sudan's lucrative gold mining sector — "also has a mutually profitable business trading gold to the UAE," De Waal said.
Tensions came to a head in November when hundreds of pro-army demonstrators took to the streets in the eastern city of Port Sudan demanding the expulsion of the Emirati ambassador.
Shortly after, Sudan's acting foreign minister Ali al-Sadiq said Abu Dhabi had expelled Sudanese diplomats from the UAE.
"We have not asked for justifications from the UAE, even though we had information of their involvement in the war," he told state television in early December.
"But they were the ones who expelled our diplomats, and so we had to respond."