Zakiur Rehman Lakhvi, the alleged mastermind of the Mumbai attacks in 2008, has refused to provide voice samples to India in relation to an investigation to indict him for involvement in the terror attacks on Indian soil, Hindustan Times reported on Sunday.

Lakhvi's lawyer – Rizwan Abbasi – told the Indian media outlet that according to Pakistan's laws, the accused's consent was necessary for a voice sample. “My client has refused in the past and will refuse again,” said Abbasi.

The development comes only a couple of days after Pakistan's and India's premiers released a joint statement from Russia, vowing to expedite proceedings of the Mumbai attack case among other sticking points.

Lakhvi was released from Rawalpindi's Adiala Jail in April this year, after a court ordered dismissal of detention orders issued against him by the Okara DCO on March 14.

The Punjab government had previously maintained that Lakhvi was detained based on 'sensitive information' provided by intelligence agencies.

Read: Lakhvi, a free man for now.

India condemned Lakhvi's release deeming it an "insult" to the victims of the 26/11 Mumbai attack.

“This is a very disappointing announcement. An insult to the victims of 26/11 Mumbai attack. The global community should take serious note of Pakistan's double-speak on terrorism,” said an Indian home ministry spokesperson who asked not to be named.

Lakhvi is among the seven persons charged with planning and helping carry out the 2008 Mumbai attacks. The six other men facing trial in Adiala Jail for their alleged involvement in Mumbai attacks are Hammad Amin Sadiq, Shahid Jamil Riaz, Younas Anjum, Jamil Ahmed, Mazhar Iqbal and Abdul Majid.

At the time of the attacks, Lakhvi was believed to be the operational head of the banned Laskhar-i-Taiba (LT) that has been accused by India of carrying out the attacks in India's financial capital.