The Federation of Islamic Associations chair said it was vital the coronial inquiry into the 2019 Christchurch terrorist attack was thorough, and given all the time it needed.
It was announced on Friday the inquiry had been delayed due to the overwhelming amount of evidence being prepared.
Association chair Abdur Razzaq said the inquiry was important for the lessons which could be learned.
"It was obvious for us that it is going to take a long time because this is one of the most complicated and most intensive coronial inquiry in New Zealand history," he said.
Razzaq said the inquiry needed more input from lawyers and forensic experts, and should be approached methodically.
The inquest was due to be heard through May and June, with families and victims to be given access to previously unavailable information.
A new date has yet to be determined.