Violence has escalated across Afghanistan now that US-led forces have all withdrawn following 20 years of military operations.

Since the withdrawal, the Taliban have taken at least eight of the country's 34 provincial capitals, and are threatening more.

More than 1,000 civilians have been killed amid fierce fighting between the Taliban and government forces in the past month, according to the UN. 

Unicef warned this week that atrocities being committed against children were growing "higher by the day".

Speaking to reporters at the White House on Tuesday, August 10,  Biden said the US is keeping the commitments it had made to Afghanistan, such as providing close air support, paying military salaries and supplying Afghan forces with food and equipment, but will not involve it's soldiers' lives anymore.

He urged Afghanistan's leaders to unite and "fight for their nation".

"They've got to fight for themselves."

In their latest major advances, Taliban militants seized two more provincial capitals - Farah city and Pul-e-Khumri - on Tuesday.

Officials said the insurgents had raised their flag in the main square and on the governor's office in Pul-e-Khumri, the capital of Baghlan province, which is located about 200km (125 miles) from Kabul.

The Washington Post also released a report saying unnamed US military officials project that the capital Kabul could fall to the Taliban within 90 days, based on US military assessments.

The Taliban have rejected international calls for a ceasefire.