The delay to the Births, Deaths and Marriages and Relationships Registration Bill was disappointing because it had already gone through the select committee process, she said. She was determined to get it passed into law during this parliamentary term.
"We encourage the minister to listen to the most important stakeholders on this issue: trans and non-binary people, their families, and human rights advocates."
The proposals relating to self-identification were made after the deadline for public submissions had closed.
That angered some conservative, religious and feminist groups, who said the implications of such a change had not been fully considered, including the possible impact on women-only spaces like prisons and refuges.
Supporters of the amendments said the ramifications had already been extensively discussed when a select committee considered a petition on the same issue in 2017. Following that petition, the select committee recommended a review to allow self-identification.
When the new Labour-led Government came to power, it referred that to the select committee considering the Births, Deaths and Marriages and Relationships Registration Bill.
When the committee reported back on the bill in August, chairman and National MP Brett Hudson said the committee had taken some effort to assess what harm such a change would create for others. It determined to a high level of confidence that it would not place others at risk, he said.
However, the Crown Law Office has since provided advice to the Government recommending further clarifications be made about when a person's sex or gender might need to be determined independently of the sex shown on their birth certificate.
These circumstances included enrolment in single-sex schools, accessing services at women's refuges and the criminal justice system.
Martin said one of the concerns was that in the absence of a medical check, the self-identification provision could be abused.
While the bill is being held up, she has asked officials to look at interim measures to make it easier and cheaper to change sex on a birth certificate.
Supporters of the law change are dismayed at the delay. Gender Minorities national co-ordinator Ahi Wi-hongi said it made no sense for the sex on different documents to be mismatched.
She believed the decision was influenced by overseas anti-trans lobby groups, which had been vocal in the often-toxic debate around self-identification in the United Kingdom.
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