The Prime Minister says her coalition government is reviewing whether it will sign up to an international agreement on migration, after National came out against the pact.
New Zealand has until December 17, when the deal will be signed, to decide whether it will support the United Nations Global Compact for Safe, Orderly and Regular Migration.
"Even though it makes it very clear that a nation maintains its sovereign rights and that it doesn't impact on our ability to act as we dictate on policy and that it's not legally binding, some have questioned that," said Jacinda Ardern. "We're seeking further advice."
Germany, Canada and 161 other countries support the UN pact, which was set up in response to the migrant crisis in Europe. The United States, Austria, Australia, Chile, the Czech Republic, Italy, Hungary, Poland, Latvia, Slovakia and the Dominican Republic oppose it.
The UN pact has become a political football for alt-right groups in the US and Europe, with the Belgian Government losing its majority over its support for the deal.
Last week, National leader Simon Bridges said National would pull New Zealand out of the compact if the Government signed it due to concerns it could restrict parliament's ability to set its own migration and foreign policy.
National was criticised for its position by human rights lawyer Sam Bookman, who wrote for The Spinoff that "At best, National seems to driving a wedge between liberal Labour and populist New Zealand First: at worst, it's making a fear mongering appeal to xenophobes and racists."
Waikato University's Alexander Gillespie said the UN deal is simply about plugging a gap in international law.
"While there is a settled and coherent international law on refugees, on migrants, there is a gap,' he said.
Professor Gillespie adds that the deal isn't doing anything particularly radical.
“Fundamentally, as there is no right to migration in international law, the Global Compact does not try to create one. Rather, it underlines the importance of sovereignty in this area.”
He said where the deal may challenge some nations is in its goal that all migrants, regardless of their legal status, receive access to basic social welfare services.
“That governments should save lives when threatened and establish coordinated international efforts on missing migrants may come as a shock to some countries that believe that mercy is a counter-intuitive policy.”
The Compact includes an objective that the detention of migrants should only be used 'as a measure of last resort' which Professor Gillespie says may be unattractive to some.
“As may the obligation to 'co-operate in facilitating safe and dignified return and readmission, as well as sustainable reintegration' of those being exited and citizens who are being returned.”
The pact underlines its commitment to 'freedom of expression' but includes a requirement that governments get involved in the 'promotion of evidence based public discourse to shape perceptions of migration'. This may be a step too far, says Professor Gillespie.
"The question New Zealand now has to resolve is whether we view the Global Compact as an essential tool that is useful and reflects our laws and values, or whether we view it as an unwelcome prod, no matter how soft, towards views we may not believe in."