Australia has evacuated another 650 people from Afghanistan in its biggest night yet of its dangerous rescue mission.
Prime Minister Scott Morrison on Tuesday revealed five overnight flights brought the total number of people extracted to almost 1,700.
"It was our biggest night," he told the Nine Network.
"The people are doing this job on the ground, they are real heroes, compassionate heroes dealing with people in the most distressing and dangerous of situations."
Mr Morrison said Australia would continue evacuation flights if the United States decided to extend the withdrawal deadline past 31 August.
"I've made no assumptions about the Taliban - we know their form," he said on Tuesday.
"We've been going like we won't be able to get another flight in the next day, so we've been trying to make every flight as successful as possible."
The prime minister said the mission would continue for as long as it could.
"If that deadline is able to be pushed out, we've made that clear to the United States that we would support that," Mr Morrison said.
"But in the meantime, we'll just keep getting on with the job."
Home Affairs Minister Karen Andrews said the situation at the gates of Kabul's airport was diabolical.
It is understood an Afghan security officer and at least seven civilians have died amid the chaos around the airport.
"We know that the situation is deteriorating hour by hour, day by day," Ms Andrews told the ABC.
She said there were multiple Taliban-controlled checkpoints on the road to the airport.
"We are expecting that there will be an escalation in violence, but it is pretty dire circumstances already there at the moment."
Britain plans to use an emergency G7 summit to lobby US President Joe Biden to extend the presence of American troops beyond the 31 August deadline.
A second repatriation flight of evacuees arrived in Melbourne from the United Arab Emirates on Monday, taking the total brought to Australia to 271.
Labor's defence spokesman Brendan O'Connor said Mr Morrison ignored multiple warnings to evacuate people before the US troop withdrawal.
"The prime minister failed to act early enough and has now been forced to admit people will be left behind," he told parliament.
Mr Morrison said the government had acted early to get people out of Afghanistan.