President Abdullah Gul on Friday approved a set of constitutional amendments that would allow female students to wear Islamic head scarves at universities.

Parliament, dominated by members of Prime Minister Recep Tayyip Erdogan's Islamic-rooted party, passed the measure earlier this month. But the legislation faces another hurdle: the secular opposition has vowed a legal challenge to the amendments on grounds that they violate Turkey's secular constitution.

The head scarf issue has polarized Turkey and exposed once again a deep gap between the Islamic-rooted government and the military-led secular establishment.

Gul, an observant Muslim, whose wife and daughter wear the Islamic style head coverings said the amendments did not violate the republic's secular principles. The changes were approved by 411 out of a 550 lawmakers "representing some 80 percent of the population," he said.

Gul said the government should put in place measures to alleviate the concerns of the secular population. Some fear the government might also try to lift the ban on head scarves in schools and government institutions.

"There is a need to understand the fears of some of our citizens and to bring to life measures that will remove these fears," a presidential statement read.