Afghanistan-based NZ journalist describes seeing Taliban militants on her way to work

A Kabul-based New Zealand journalist says she saw armed Taliban militants patrolling the streets on her way to work on Monday morning (local time) - a day after the group seized control of Afghanistan's capital.

New Zealand Defence Force troops will leave on Wednesday morning to help desperate civilians in Afghanistan after the Islamist militants entered Kabul virtually unopposed.

"I actually felt safer today, under day one of Taliban control," said Al Jazeera journalist Charlotte Bellis, a New Zealander. "I don't know if that's naive of me or not but about 1000 special forces came in from the Taliban overnight."

Chaos unfolded at Kabul airport overnight as people desperately flooded the tarmac in an attempt to flee the war-torn nation. At least five people were reported killed, forcing a pause in evacuation flights. 

"The Taliban were actually working with the Americans - trying to scare people away from the airport by shooting in the air around it," Bellis explained. "Some people ran away but then the Americans got scared and shot at the Taliban, and killed a couple of them."

She told The AM Show there was no sign of the situation improving at Kabul airport.

"It's still incredibly chaotic - there are still thousands of people on the tarmac. They've just completely overwhelmed the tarmac."

Earlier, US President Joe Biden broke his silence on the Afghanistan crisis. He's faced days of mounting criticism over his decision to withdraw US forces after 20 years of war - the nation's longest.

But Biden again defended the withdrawal, saying the Afghan people needed to fight their own battles.

"The truth is: this did unfold more quickly than we anticipated," he said. 

"So what's happened? Afghanistan political leaders gave up and fled the country. 

"The Afghan military gave up, sometimes without trying to fight."

Former New Zealand Prime Minister Helen Clark, who was at the helm when the US first sent forces to Afghanistan - and made the decision to send in Kiwi troops - said she wasn't surprised by the speed of the Taliban takeover.

Speaking to The AM Show, Clark said the situation was a diplomatic disaster and Afghanistan's future was looking grim.

"This is catastrophic… it's a very sad day for Afghanistan… and the US is now left without leverage to influence that future." 

She said the Taliban couldn't be trusted.

"The Taliban are not very good at keeping their word - they wanted power, so they were probably prepared to say just about anything."

On Monday, New Zealand Defence Minister Peeni Henare said 40 Kiwi troops would be sent to Afghanistan on Wednesday.

From there, they will assist with ongoing evacuation operations, he said.