President Ghani flees, Afghan vice president announces temporary replacement.

Afghan Vice President Amrullah Saleh said Tuesday that he was still in Afghanistan and became the "legitimate interim president" after President Ashraf Ghani left the country when the Taliban seized the capital Kabul.

Saleh said at a security meeting chaired by Ghani last week that he was proud of the armed forces and the government would make every effort to strengthen the resistance against the Taliban.

However, Afghanistan fell to the Taliban in a matter of days, not months predicted by US intelligence.

In a series of tweets on Tuesday, Salah said it was "useless" to argue with US President Joe Biden who had decided to withdraw US troops.

He called on Afghans to prove that Afghanistan "is not Vietnam and the Taliban are not even like the Vietcong."

A video of a desperate Afghan trying to board a US military plane as it is about to take off harks back to a 1975 photo of people trying to get into helicopters in Saigon as the US pulled its troops out of Vietnam.

Saleh said that unlike the US and NATO "we don't lose heart & see great opportunities ahead. The bullshit warning is over, JOIN THE RESISTANCE."

Saleh, whose whereabouts are unknown, confirmed that he would not "subject under any circumstances" to the "Taliban".

According to him, he would "never betray" Ahmad Shah Massoud, the leader of the Northern Alliance who was assassinated by two al Qaeda members before the September 11, 2001 attacks on the United States.