The U.S., Australia and Britain are urging people to move away from Kabul airport due to a terror threat.
Thousands of Afghans and foreign nationals have gathered outside the airport in recent days hoping to be able to leave the country.
Taliban fighters had promised to provide security in the area, but there have been intelligence reports of an imminent threat from Islamic State militants.
A threat which NATO and its allies say cannot be ignored.
Australia's Foreign Affairs Minister Marise Payne:
"Our clear travel advice is now, do not travel to Hamid Karzai International Airport and if you're in the area of the airport, move to a safe location and await further advice. Afghanistan remains highly volatile and dangerous. Be aware of the potential for violence and security threats with large crowds. There is an ongoing and very high threat of terrorist attack."
Pressure to evacuate those who helped Western nations during the 20-year war against the Taliban has intensified with U.S. and allied troops due to leave next week.
The Taliban says foreign troops must stick to that deadline.
Since they took over Kabul 11 days ago, the U.S. and its allies have mounted one of the biggest air evacuations in history.
More than 88,000 people, including 19,000 in the past 24 hours, have been got out.
U.S. Secretary of State Anthony Blinken said on Wednesday around 1,500 Americans remained in the country.
He said there was no deadline for the effort to help those who wanted to leave.