Pakistan's Supreme Court has declared unconstitutional a bill passed by a staunchly Islamic province to enforce Islamic values on society with the help of so-called religious police.

The Supreme Court ordered the governor of North West Frontier Province not to sign the bill in its present form.

The bill was passed by the provincial assembly where hardline religious parties are in a majority. But it must be approved by the provincial governor, who is appointed by Islamabad, before it can become law.

The issue was referred to the Supreme Court by President Pervez Musharraf who has vowed to rid society of Muslim extremism.

The court spent four days on the federal government's challenge to the legislation. The nine-member bench ruled that many of the provisions in the bill violate the country's 1973 constitution.

Some information for this report provided by AP and AFP.