The United Nations says a Taliban order has barred Afghan women from working for the body.
The UN said that while there has been no written communication, the Taliban have informed them verbally.
It has told its Afghan staff - men and women - to not report to work for 48 hours until it has clarity on the matter in meetings with the Taliban.
The UN has called the move "unacceptable and frankly inconceivable".
BBC says Female workers play a vital role in on-the-ground aid operations, particularly in identifying other women in need.
The UN has been working to bring humanitarian aid to 23 million people in Afghanistan, which is reeling from a severe economic and humanitarian crisis.
Foreign female workers are exempt from the ban but if implemented, this would be the most significant test of the future of UN operations in Afghanistan, and the relationship between the organization and the Taliban government.
There has been an increasing clampdown on women's freedoms since the Taliban seized power in 2021.
