The first US troops are arriving in Afghanistan to help diplomatic staff and others to leave, as many countries scramble to evacuate workers and citizens amid a rapid Taliban advance.
Militants yesterday, captured Pul-e-Alam, capital of Loghar province, just 80km from the capital Kabul.
The UN chief said the situation is spinning out of control with devastating consequences for civilians.
More than 250,000 people have been forced to leave their homes so far.
The Taliban advance comes as US and other foreign troops withdraw after 20 years of military operations.