Sudan's de facto leader Abdel Fattah al-Burhan left Saturday for a visit to Uganda, the ruling Sovereign Council said, in his latest trip abroad as battles raged in Khartoum.

The African country has been at war since fighting erupted in the capital between the regular army led by Burhan and the paramilitary Rapid Support Forces commanded by his deputy-turned-rival Mohamed Hamdan Daglo.

Clashes around Khartoum's military headquarters -- where Burhan had been holed up until last month -- had seen a brief two-week respite before flaring again, with the RSF showering it with artillery fire, residents said.

Burhan is due to meet Ugandan President Yoweri Museveni in Kampala, with whom he would discuss "bilateral ties and issues of common importance", the Sovereign Council said in a statement.

It is the Sudanese general's sixth trip abroad since he made his first public forays late last month, including visits to Egypt, South Sudan and Turkey, among other countries.

At least 7,500 people have been killed since the conflict broke out on April 15, according to a conservative estimate from the Armed Conflict Location & Event Data Project.

The war has uprooted more than five million people, including one million who fled across borders, according to United Nations figures.

Eyewitnesses on the ground told AFP they heard clashes in central Khartoum, with one resident saying the RSF "is firing heavy artillery" at the army headquarters.

Neither side has been able to gain the upper hand in the conflict, with the army controlling the skies and Daglo's fighters embedding themselves in residential areas.

Witnesses have noted an increase in the intensity of air strikes, and consequently the civilian death toll, as the army seeks to regain control of parts of the capital.

Burhan has been Sudan's de facto leader since the ouster of longtime autocrat Omar al-Bashir in 2019, when he was appointed head of the Sovereign Council of military and civilian figures tasked with steering the transition to a fully-fledged democracy.