In a lengthy document issued by the Taliban’s education authority, they also ordered that female students should only be taught by women, but if that was not possible then "old men" of good character could fill in, reports AFP news agency.

Several private universities mushroomed in Afghanistan ever since Taliban's earlier rule ended in 2001.

There was no order for women to wear the all-enveloping burqa in the new regulations issued late Saturday, but the niqab effectively covers most of the face anyway, leaving just the eyes exposed, reported AFP.

"Universities are required to recruit female teachers for female students based on their facilities," the decree said as quoted by AFP, adding that men and women should use separate entrances and exits. If it is not possible to hire women teachers, then colleges "should try to hire old men teachers who have a good record of behaviour".

"Practically, it is a difficult plan -- we don't have enough female instructors or classes to segregate the girls," a university professor, who asked not to be named, told AFP.

"But the fact that they are allowing girls to go to schools and universities is a big positive step," he told the agency.