The Auckland Council is being accused of failing to consult religious and cultural groups on rules around its proposed burials and cremations.
The group Multicultural New Zealand said the Council did not actively seek the views of various groups when it formulated the draft bylaw.
Under the bylaw, families will need permission to scatter their loved ones' ashes in a public place.
Approval will be needed from the Council or from a Wahi Tapu Maori committee.
Only an authorised person will be able to fill in a grave, and only two people will be allowed to view a casket being placed in a cremator.
An advisor to to Multicultural New Zealand, Joris de Bres, said little thought has been given to religious and cultural issues.
He said his organisation has written to the Mayor asking for the process to be put on hold to allow for further consultation.
Heavy-handed and unnecessary
The Labour Party says the Council's plan is heavy-handed and unnecessary.
Its Ethnic Affairs spokesperson, Phil Goff, said there has been a lack of consultation about the proposed changes.
He said the proposals would impose time delays and extra expenses on grieving families.