A bench of justices AS Oka and AS Gadkari cautioned the agency that if it didn't change its conduct, the high court will be forced to stay the trial in the case before the special court.
"You realise that a stay on the trial will end up benefiting the accused. However, if you continue your delay tactics, this court will be left with no choice," the bench said.
The observations came after NIA repeatedly justified the use of photocopies of some statements of witnesses and confessions of accused persons in the case.
On the previous hearing, the bench had observed that the special court should not have allowed the use of photocopies since there was no evidence to prove that the photocopied documents were authentic copies of the original, certified statements.
It had told NIA counsel Sandesh Patil that the agency should have pointed out the problem to the special court then and there and taken the correct legal stand by not relying on photocopies.
However, Patil said Tuesday that since the special court had approved the use of the photocopies, the high court must dismiss the appeal challenging the special court order.
The bench was hearing an appeal filed by Sameer Kulkarni, a co-accused in the case, challenging a 2017 order of the special court that permitted the use of photocopies of statements of witnesses and confessions of accused as secondary evidence in the case.
It is likely to continue the hearing next Monday.
Kulkarni and his co-accused in the case, Prasad Shrikant Purohit, have filed several appeals in high court challenging various interim orders of the special court.