Turkey's parliamentary speaker has called for changes to the country's political system in hopes of reducing the powers of Turkey's top court.

Koksal Toptan suggested a new constitution and re-installing the upper house of parliament, or senate. He said a two-chamber parliamentary system will ease pressures on Turkey's constitutional court.

Toptan spoke a day after Turkey's ruling AK party accused the constitutional court of overstepping its authority by annulling a law that allowed Muslim headscarves to be worn at universities.

A party official said the court violated Turkey's separation of powers by interfering in parliament's authority to pass laws.

On Thursday, the court annulled constitutional forms that lifted a decades-old ban on wearing headscarves at schools. It said the reforms violate the country's secular principles.

U.S.-based Human Rights Watch today criticized the court's ruling as a blow to freedom of religion.

Turkey's President Abdullah Gul approved the constitutional reforms in February, but many universities defied them and blocked female students with headscarves.

The Islamist-rooted AK party says wearing headscarves at universities should be a matter of personal choice.

Turkey banned headscarves in public places, schools and universities in the 1980s.