Khalid Abdelaziz

The Sudanese army seized full control of the Presidential Palace in downtown Khartoum, it said in a statement, in one of the most symbolic gains in a two-year-old conflict with a rival armed group that has threatened to partition the country.

Sudan's Rapid Support Forces (RSF) and allied groups signed a transitional constitution on Tuesday that takes them a step closer to setting up a parallel government during a two-year-old war with the army that threatens to split the country.

Gum arabic, a vital ingredient used in everything from Coca-Cola to M&M's sweets, is increasingly being trafficked from rebel-held areas of war-torn Sudan, traders and industry sources say, complicating Western companies' efforts to insulate their supply chains from the conflict.

A parallel government being set up by Sudan's Rapid Support Forces (RSF) aims to grab diplomatic legitimacy from its army-led rival and ease access to advanced weaponry, politicians who back it and paramilitary sources told Reuters.

Satellite images show at least three drones and the construction of hangars at an airport in South Darfur held by Sudan's Rapid Support Forces (RSF), evidence of the continuing stream of increasingly advanced weapons fuelling a devastating war.

The RSF has seized most of the western Darfur region and swathes of the Kordofan region in an almost-two-year war, but is being pushed back from central Sudan by the Sudanese army.

Sudan's Rapid Support Forces have attacked the famine-stricken Zamzam displacement camp, residents and medics say, as the paramilitary tries to tighten its grip on its Darfur stronghold while losing ground to the army in the capital, Khartoum.

The United Arab Emirates called on Tuesday for a ceasefire in Sudan during the coming holy month of Ramadan, a UAE official said, a call rejected by the Sudanese army, as the country's civil war approaches the two-year mark.

The RSF, which has said it would support the formation of a rival civilian administration, has retreated, overpowered by the army's expanded air capacities and ground ranks.

At least 54 people were killed and 158 wounded on Saturday in a strike by Sudan's paramilitary Rapid Support Forces (RSF) on a market in the city of Omdurman, the health ministry said in a statement.