NEW DELHI - Islamic courts have no legal authority in India, the country's Supreme Court ruled Monday, saying Muslims cannot be legally subject to a parallel religious authority.

Individuals may abide by Shariah court rulings if they wish, but cannot be legally forced to do so, Judge C. K. Prasad said.

"No religion is allowed to curb anyone's fundamental rights," he told the court, giving the decision of a two-judge bench. Indian law does not recognize Shariah court rulings, he said.

The court was responding to a petition filed in 2005 by a lawyer who said the Shariah courts should be disbanded for running a parallel judicial system in a country with 150 million Muslims among its 1.2 billion population.

Islamic courts wielded considerable influence in Muslim-dominated areas, and people often felt powerless to oppose their rulings, the petitioner Vishwa Lochan Madan argued.

The Supreme Court rejected Madan's request to disband the Shariah courts, saying there was no point if their edicts had no legal sanction. People were still free, however, to voluntarily consult an Islamic court for arbitration in personal matters.

Muslim leaders denounced the ruling.