The UN Human Rights Office in the Pacific is working with the Tongan government to help them move towards ratifying a convention.
Over a month ago Tonga announced it would ratify the Convention on the Elimination of all forms of Discrimination on Women but it has been delayed by opposition from church leaders.
They expressed concern it would lead to same sex marriage and abortions in the country as CEDAW refers to the right of a woman to choose her spouse and family planning.
In response the government is planning law changes to prohibit same sex marriage and will add reservations or conditions to their ratification to allow for cultural considerations.
The Deputy Regional Representative Catherine Phuong says her office is aware of the situation.
"We are aware that there are some political sensitivities and sometimes ratification requires more discussion but is important that government and partners understand what the convention is about. We remain hopeful that ratification will proceed. CEDAW is a very important convention. It's one of the most ratified human rights treaties in the world because it addresses an issue that is important to all of us."
Tonga is one of only seven nations which haven't ratified CEDAW - the others include Iran, Sudan, Somalia and the United States.