NEW DELHI (AFP) - India's Supreme Court on Wednesday ordered authorities to provide protection to two sisters facing alleged rape threats by a local council after their brother eloped with a high caste woman.

The order comes a month after one of the sisters from northern Uttar Pradesh state petitioned the top court seeking protection for her family from the dominant caste council, or "khap panchayat", which allegedly threatened them to be raped and paraded naked as a "punishment" for their brother's relationship.

"We deem it appropriate to direct the Delhi Police to take such appropriate measures as are necessary and sufficient to protect the life and liberty of the petitioner and the members of her family," justices J. Chelameswar and A.M. Sapre said in their order.

The court also ordered the release of their brother from prison on charges of drug trafficking, which the family claims are fabricated.

"The court has recognised our concern and we think this is the first step towards justice," Vivek Singh, representing the sisters in court, told AFP.

The family, from the lowest "untouchable" Dalit caste, has been forced into hiding since May, after their village's dominant Jat caste accused the brother of abducting the married woman.

The plight of the sisters aged 23 and 15, who fled their village in Bhagpat district for the capital New Delhi, some 50km away, has caused global criticism over threats to women in India.

Rights group Amnesty International, which launched an online petition to protest against the alleged khap panchayat threat, hailed the court's move, saying it offers hope the family "will finally get justice".

"The last few months have been a harrowing time for this family," Amnesty International India said in a statement.

Bhagpat police have denied that the khap panchayat had issued rape threat against the sisters.

Village councils and "khap panchayats" - separate informal councils composed of elders - exert enormous influence over rural life, particularly in northern India.

Although they carry no legal weight, khaps can be highly influential and have been blamed for numerous abuses such as the sanctioning of "honour killings" of couples defying tradition.

Branded "kangaroo courts" by critics, they have also been known to hand down public beatings for perceived crimes.