Senior German political sources have told the BBC that British attempts to evacuate its embassy staff from Sudan at the weekend delayed efforts by other countries to rescue their own citizens.
They allege British forces landed in Sudan without the Sudanese army's permission - as other European nations were hoping to airlift citizens to safety.
The UK Ministry of Defence (MoD) described that as "complete nonsense".
Germany, among others, had planned to use the airfield north of Khartoum from which subsequent evacuation operations have been conducted.