The anti-terrorism court in Islamabad recorded no progress during the last hearing on Saturday as the judge, Kausar Abbas Zaidi, was on leave. The next hearing was fixed for August 31.
Lawyer Riaz Akram Cheema, part of the team defending Lakhvi and the other accused, said this was the first time that the trial of the accused has been deferred for six weeks.
He criticised the postponement, saying that an anti-terrorism court cannot put off any case for more than two weeks.
The seven suspects include Lashkar-e-Taiba commander Lakhvi, who allegedly masterminded the attacks that killed 166 people in India's financial hub in November 2008.
Pakistan has acknowledged that the conspiracy behind the attacks was hatched in the country. The seven men were arrested shortly after the attacks but their trial has progressed at a snail's pace.
LeT operative Ajmal Kasab, the only surviving attacker, was recently hanged by India. New Delhi has demanded that Islamabad should expedite the trial of the seven suspects to show that it is serious about countering terrorism.
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