Azhar Chaudhry, Prosecutor of Pakistan's Federal Investigation Agency, told NDTV, "Once we get the order we will appeal against bail plea and demand a stay order."
Lakhvi was granted bail on Thursday by an anti-terror court in Islamabad which said the prosecution has been unable to provide evidence against him. He was among seven people arrested in the Mumbai attacks trial in Pakistan in 2009.
India has said it "cannot accept" that Lakhvi is being released on bail.
"It will serve as a reassurance to terrorists who indulge in heinous crimes. Let us not forget that the financing of the attack was done in Pakistan," said Syed Akbaruddin, spokesman in the ministry of external affairs.
Home Minister Rajnath Singh said he hopes Pakistan will appeal in a higher court and "cancel the bail." He said, "This decision is unfortunate. I believe Pakistan didn't do enough; India has provided enough evidence (on Lakhvi's role in the 26/11 attacks)."
Lakhvi, 54, is accused of being one of the key plotters of the 26/11 Mumbai attacks and also of training and handling the 10 Lashkar terrorists who sneaked into Mumbai and killed 166 people. The chargesheet against him says, "Lakhvi and the others organised four training camps to train the 26/11 terrorists, supplied weapons and explosives to them."
This week, it pledged its support to Pakistan which is grappling with the massacre of 132 children in a Peshawar school. Prime Minister Narendra Modi reached out to Pakistan Prime Minister Nawaz Sharif and said the tragedy was "a call for our two countries and all those who believe in humanity to join hands to decisively and comprehensively defeat terrorism."
Lakhvi co-founded the Lashkar-e-Taiba, which is banned in Pakistan. Another founder, Hafiz Saeed, accused by India of masterminding the 26/11 attacks and one of the world's most wanted men, already roams free in Pakistan and yesterday appeared on national TV blaming India for the massacre of the children at the Peshawar school and vowing revenge.
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