Legislation has been drafted to ban so-called gay conversion therapy by the end of the year, the Herald understands.
Justice Minister Kris Faafoi is expected to make an announcement on the topic this afternoon.
Conversion therapy seeks to change lesbian, gay, bisexual or transgender (LGBT) people's sexuality or gender identity using therapy, drugs or other methods.
Following years of advocacy, by groups such as Ending Conversion Therapy, Labour had campaigned on banning the practice and make it a criminal offence to advertise, offer or perform it, ahead of last year's election.
However in the months after the election the Government went silent on the issue,
Activist groups reignited the conversation, and Green Party MP rainbow spokeswoman Elizabeth Kerekere launched a petition in February accumulating 157,764 signatures in a matter of days, presented to Parliament shortly after the ban timeline was announced.
Faafoi announced shortly after a timeline, saying the Government planned to bring legislation to Parliament by the middle of the year, which would see conversion therapy outlawed by the end of this year, or by February 2022.
Conversion therapy is a western practice based on a belief people with diverse sexual orientations or gender identities are abnormal and should be changed so they fit within hetero-normative standards.
It can take place in health clinics, but mainly involves faith-based groups providing counselling, prayer and group support activities.
Waikato University senior lecturer in psychology Dr Jaimie Veale previously told the Herald there was no conclusive data about how many people had been through so-called gay conversion therapy in New Zealand, although there was plenty of anecdotal evidence.
A survey of trans people "Counting Ourselves", of which Veale was principal investigator, found 17 per cent of respondents, or one in six, experienced a health professional trying to stop them from being trans or non-binary.
In Australia, a 2018 study found 10 per cent of Australians who were attracted to people of the same sex or were gender diverse were vulnerable to conversion therapy practices.
"So we know these practices are occurring, but by their very secretive nature we don't know how widespread it is, and there has been little resources put towards finding out," Veale said.
"But we know it is all based on this idea that it is a mental disorder, a pathologising view, and that these are really very harmful practices."
In banning conversion therapy New Zealand joins a growing group around the world, including several Australian states.
Queensland was the first to bring in a ban in August last year, followed by the Australian Capital Territory. But the widest-reaching is that adopted in Victoria in February.
Under the reforms, anyone found trying to suppress or change another person's sexuality or gender identity faces up to 10 years' jail or fines of almost $10,000 if it can be proved beyond reasonable doubt that their actions caused serious injury.
Gay conversion therapy would also become a form of domestic violence, and complaints that did not meet the criminal threshold would be investigated by a separate commission.
Activists in New Zealand have called for a similar bill to be adopted here.
While the bill in Victoria has been described by advocates as "world-leading", some critics have called it an attack on religious freedom and some health professionals were concerned the broad wording could prevent "ordinary conversations" around sexuality.
In 2018, after 20,000 people signed two petitions calling for the ban, Labour MP Marja Lubeck entered a bill in the members' ballot seeking to prohibit the practice.
Last year the Justice Select Committee recommended to delay a decision because of concerns about rights to freedom of expression and religion.
At the time Finance Minister Grant Robertson said Lubeck's bill would be adopted as a Government bill if Labour was re-elected, and suggested NZ First didn't support banning the practice during the last term.