ISLAMABAD: State prosecutor Azhar Chaudhry said Monday he had been forced to delay his appeal against a court order which grants bail to Zakiur Rehman Lakhvi, the alleged mastermind of the 2008 terror attacks in Mumbai.

A judge in Islamabad's anti-terror court last week had granted bail to Lakhvi, accused for the siege in India's commercial capital that left 166 people dead and was blamed on the banned Pakistan-based militant group Lashkar-i-Taiba (LT).

Read: Mumbai attack 'mastermind' Lakhvi detained under MPO

The bail decision had triggered a furious response from New Delhi and Pakistani prosecutors had swiftly announced they would appeal against it.

The challenge was due to be filed on Monday but state prosecutor Mohammad Azhar Chaudhry told AFP he had been unable to proceed.

“I have not yet received a copy of the court (bail) order, which is essential to complete legal formalities,” he told AFP.

Chaudhry said he would challenge the bail order after examining it.

Relations between Pakistan and India had worsened dramatically after the Mumbai carnage, in which 10 gunmen attacked luxury hotels, a popular cafe, a train station and a Jewish centre.

Lakhvi remains in custody in the high-security Adiala prison in the garrison city of Rawalpindi after the authorities ordered his detention, following the court's bail decision, under public order laws.

Indian Prime Minister Narendra Modi told lawmakers last week that the bail order came “as a shock to all those who believe in humanity the world over”.

It took the authorities three days to regain full control of Mumbai after the carnage started and New Delhi has long said it has evidence that “official agencies” in Pakistan were involved in plotting the attack. Islamabad denies the charge.

After the attack, seven Pakistani suspects were charged with its planning and financing but the failure to advance their trials has been a major obstacle to improved ties between Pakistan and India.

Delhi accuses Islamabad of prevaricating over the trials, while Pakistan has claimed that India failed to hand over crucial evidence.