Another 472 citizens and Afghans with visas were extracted on four Australian flights on Sunday as a dangerous rescue mission continues.

Since August 18 more than 1000 people have been lifted out of Afghanistan as part of Australian efforts to evacuate people from the Taliban-controlled nation.

US President Joe Biden is hopeful extending the withdrawal deadline beyond August 31 will not be necessary but hasn't ruled out the idea.

Foreign Minister Marise Payne said Australia was part of talks with the US about a potential extension.

"If they are to be extended we are absolutely ready to support a continuing operation at Hamid Karzai International Airport," she told reporters in Canberra.

Senator Payne described the situation as a punishing environment for people trying to get to the airport and those working on evacuations.

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 Scott Morrison ignored multiple warnings time was running out 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 rejected the claim and accused the opposition of engaging in politics on a day of reflection about the war.

"This government has been working steadfastly, consistently, and urgently for years to bring people out of Afghanistan," he said.

Afghans who guarded Australia's embassy in Kabul have been granted humanitarian visas after earlier being denied a separate entry permit.

Home Affairs Minister Karen Andrews said the security staff were not eligible for the locally-engaged employee program.

"We have processed many of those overnight," she told reporters in Canberra on Monday.

Ms Andrews said emails had been sent to people advising them to head to the gate at Kabul airport.

The minister said all 100 embassy workers had been granted humanitarian visas.

Ms Andrews denied granting humanitarian visas to the embassy staff was a last-minute rush, saying work had been under way for months.

"It has certainly escalated because of this significantly deteriorating situation in Afghanistan at the moment," she said.

She said Australian officials needed to run security checks which meant processing took some time.

"I am not, as the home affairs minister, keen to make mistakes in processing people so quickly that we cannot run even the most basic of security checks over them."

Opposition Leader Anthony Albanese said confusion over security guards, who were told to contact a migration agent on Saturday, was sheer callousness.

"It contrasts starkly with the leadership being exemplified by veterans who served in Afghanistan who have rallied behind their Afghan mates," he told parliament.

Australian Associated Press