He was asked, may Allah raise his rank, about the ruling on the awrah of a woman with another woman.

He answered: The awrah of a woman with another woman is like the awrah of a man with another man, meaning what is between the navel and the knee.

But this does not mean that women may wear short clothing in front of each other that only covers between the navel and the knee, because none of the people of knowledge ever said this.

The meaning is that when a woman is wearing loose, wide and long clothing, and then something from her lower leg or her upper chest or something similar becomes uncovered in front of another woman, then there is no sin in that.

Shaykh al Islam Ibn Taymiyyah mentioned that the clothing of women in the time of the Prophet ﷺ was covering from the hand palm to the ankle of the foot.

And it is known that if the door were opened for women to shorten their clothing, this would lead to many harms and the situation would get worse until women would begin to wear clothing far from Islamic clothing, similar to the clothing of the women of the disbelievers.

Majmu’ Fatawa wa Rasail Muhammad ibn Salih al-‘Uthaymeen (12/267)