The US ambassador to Sudan has been forced to take shelter after sustained fighting broke out in the capital Khartoum, as tension between the military and powerful paramilitary forces escalates.

John Godfrey said he and embassy staff were sheltering in place as heavy firing was heard in a number of areas.

The Rapid Support Forces militia claimed they had seized Khartoum airport, as well as an airport and air base in the northern city of Marawi.

It accused the army of attacking its forces at one of its bases, while the Sudanese Army said the fighting broke out after RSF troops tried to attack its forces in the southern part of the capital.

In a statement, the military declared the RSF a “rebel force”, describing the paramilitary’s statements as “lies”.

Mr Godfrey said the escalation was “extremely dangerous” and called on senior leadership to stop the clashes.