Lees-Galloway said the issue of automatic residency was being considered.
"There are a number of matters that have been raised by these unprecedented events. We're turning our mind to all of these issues," he said today.
Any decisions would be announced in the near future.
Delamere, in an open letter to Lees-Galloway, suggested residency should be granted to all affected families which had already applied and it should be offered to those who had not yet done so.
He and most New Zealanders believed the people killed in the attacks died as New Zealanders.
"To not offer the victims' families the grant of residence will just give the murderer another reason to celebrate his evil," Delamere said.
Many of the 50 people killed were foreign nationals with families here on temporary visas.
Migrants from Malaysia, Bangladesh, Indonesia, Pakistan, Turkey, India, Jordan, Saudi Arabia are believed to be among those killed, injured or missing.