Gareth Bostock, manager of Internal Affairs' "Financial Integrity Team", said there had been an extensive outreach and education programme over the past two years.
"The department's focus initially will be to support regulated parties understand and comply with the new regulatory reporting requirements.
"As increasing levels of understanding and compliance take effect the department expects to take increasingly firmer responses to non-compliance," Bostock said.
Breaches of the act carry a maximum penalty of a two-year jail sentence and fine of up to $300,000 for an individual and $5 million for body corporates.
Bostock said the main challenge for the DIA in carrying out its role would be the large number and variety of entities it had to supervise.
The Reserve Bank - which is overseeing banks, life insurers and non-bank deposit takers - said because reporting entities have had a time to get ready, there would be no transition period.
"This means that reporting entities must comply with their obligations on 30 June 2013," a spokesperson said.
All reporting entities would be audited every two years or at any other time at the request of their supervisor, the bank spokesperson said.
"Based on the bank's interactions to date, it considers its regulated entities are relatively well prepared for the commencement of the AML regime."
The FMA expected all the businesses it was supervising would be compliant by June 30.
"Due to the long lead in time and the work we have already done with reporting entities, FMA does not expect the enforcement of AML/CFT to present any major challenges," said spokesperson Tony Reid.
Reid said where non-compliance was identified, the FMA would use a range of tools to deliver "a timely, effective and proportionate response".
"We may undertake further inquiry or expect a reporting entity to adjust its compliance and will follow up to ensure that this is done.
"In some cases, notices, warnings or enforceable undertakings may be used. Further non-compliance could result in stronger action, such as civil or criminal prosecution," Reid said.
The FMA will oversee issuers of securities, brokers, financial advisers, trustee companies, collective investment schemes and futures dealers.
Reid said the authority had been engaging with industry players via road shows, seminars, questionnaires, one-on-one visits and targeted presentations.
"FMA has visited over 100 medium/large reporting entities to assess preparedness for the regime," he said.
The AML/CFT Act aims to help boost New Zealand's financial reputation overseas and meet international obligations.