President Joe Biden said on Thursday that the Taliban have not changed but are going through an "existential crisis" about whether they want legitimacy on the global stage as they have taken over Afghanistan.

In an interview on ABC's Good Morning America, Biden said that he’s not sure the Taliban want to be recognised by the international community as being a legitimate government.

He also said that the threat from Al-Qaeda and their affiliate organisations is greater in other parts of the world than it is in Afghanistan, adding that it’s not rational to ignore the looming problems posed by Al-Qaeda affiliates in Syria or East Africa, where he said the threat to the US is significantly greater.

"We should be focusing on where the threat is the greatest," Biden said, in defense of the US withdrawal from Afghanistan.

Biden also pushed back against concerns about the treatment of women and girls in the country, arguing that it’s not sane to try to protect women's rights around the globe through military force.

"Instead, it should be done through diplomatic and international pressure on human rights abusers to change their behavior."

Biden had on Monday warned the Taliban not to disrupt or threaten the evacuation of thousands of American diplomats and Afghan translators at Kabul airport.

The response to any attack would be “swift and forceful”, Biden had said in a televised address from the White House.

He also defended the US pullout, saying he stood by the policy and that it was time to leave after 20 years of conflict.

“I stand squarely behind my decision. After 20 years, I’ve learned the hard way that there was never a good time to withdraw US forces,” he said.

The Taliban had declared the war in Afghanistan over on August 16 after taking control of the presidential palace in Kabul.

“Now it's time to test and prove, now we have to show that we can serve our nation and ensure security and comfort of life,” Taliban co-founder Abdul Ghani Baradar had said in a video posted on social media.