( BBC ) - The Turkish parliament is expected to amend the country's constitution to ease the ban on women wearing Islamic headscarves in universities.
The issue is deeply divisive in Turkey, where the state is strictly secular, and protests are expected.
The government says secularism means many girls are denied an education.
But the secular establishment, including generals and academics, sees this as a first step to allowing Islam to figure more largely in public life.
Opposition parties have vowed to challenge the changes in the constitutional court if, as is expected, they are passed on Saturday.
The Islamist-rooted AK Party has a safe majority in the Turkish parliament and the proposals were passed in an initial parliamentary vote on Wednesday, carried by 401 in favour to 110 against.
A strict headscarf ban has been in force in Turkish universities since 1997. The ban came after the staunchly secularist military had exerted pressure to oust a government it saw as too Islamist.
The proposed changes state that only traditional scarves will be permitted in universities, tied loosely under the chin. Headscarves that cover the neck will still be banned, as will the all-enveloping burka, or chador.
Ural Akbulut, rector of the Middle East Technical University, in Ankara, says the changes represent the imposition of religious beliefs into the constitution.
"We say it will damage secularity," he told the BBC. "Once you do that - we believe you damage democracy."
The BBC's Sarah Rainsford says those who wear the headscarf dismiss that as paranoia.
They say the scarf is simply an expression of their personal religious belief.
As Turkey's population is predominantly Muslim, two-thirds of all Turkish women cover their heads, meaning thousands miss out on the opportunity to attend college. Many Turks argue that is unfair and there is widespread public support for the move.
But tens of thousands of people against lifting the ban are expected to join protest rallies in the capital on Saturday.