"The problem is increasing markedly on a monthly basis.
"We now believe a public Commission of Inquiry, to ensure all aspects of the methamphetamine problem, including the growth of organised crime that accompanies it, is essential.
"Such an inquiry should be focused on making recommendations around legislation, resourcing and establishing early warning systems to detect future drug threats in New Zealand," Mr O'Connor said in a statement.
The Police Association had written to Prime Minister Helen Clark requesting such an inquiry.
The UN survey said New Zealand and Australia were second only to Thailand on the percentage of the population using methamphetamine.
It was reported 3.7 per cent of the population of New Zealand and Australia abused the drug.
Australia was also a world leader on ecstasy abuse, with 2.9 per cent of its population abusing the drug.
New Zealand was not far behind on 2.3 per cent.
- NZPA
United Nations Office on Drugs and Crime