Three civilians died Saturday in battles between Sudanese paramilitaries and the regular army, which said it launched air strikes against them, sparking global calls for calm in a country that has seen decades of unrest.

The paramilitaries said they were in control of the presidential place as well as Khartoum airport, claims denied by the army, as civilian leaders called for an immediate ceasefire to prevent Sudan's "total collapse".

The doctors' union reported the three civilian deaths, including at Khartoum airport and in North Kordofan state. At least nine others were wounded, the medics said.

Violence erupted after weeks of deepening tensions between military leader Abdel Fattah al-Burhan and his deputy, paramilitary commander Mohamed Hamdan Daglo, over the planned integration of Daglo's paramilitary Rapid Support Forces (RSF) into the regular army.

The integration was a key element of talks to finalize a deal that would return the country to civilian rule and end the political and economic crisis sparked by their 2021 coup in one of the world's poorest countries.

Created in 2013, the RSF emerged from the Janjaweed militia that then-president Omar al-Bashir unleashed against non-Arab ethnic minorities in the western Darfur region a decade earlier, drawing accusations of war crimes.

US Secretary of State Antony Blinken said he was "deeply concerned" and urged both sides to "stop the violence immediately", a call echoed by the United Nations, African and Arab regional blocs, and the European Union.

Russia's foreign ministry said there was "serious concern in Moscow," which called for urgent steps toward a ceasefire.

The army said it carried out air strikes and destroyed two RSF bases in Khartoum.

The latest deaths, during the Muslim holy fasting month of Ramadan, came after more than 120 civilians had already been killed in a crackdown on regular pro-democracy demonstrations since the coup.