A statistics professor says cases in India have almost tripled since the travel suspension was announced and allowing travel to resume would be difficult.
With the two-week halt on flights from India about to expire, the Government is considering whether to create a traffic-light system to pause flights from countries particularly affected by Covid-19.
Covid-19 Response Minister Chris Hipkins yesterday said just because a country has lot of cases doesn't automatically mean it is in the red-zone but rather the risk to New Zealand is taken into account.
Statistics professor and principal investigator at Te Pūnaha Matatini Professor Michael Plank told RNZ arrivals from the vast majority of countries should remain subject to a 14-day quarantine.
"It's really only countries like Australia where the virus has been eliminated we could potentially think about putting into a green-zone.
"On the other end of the spectrum, as we've seen recently with India, when you start to see a high percentage of arrivals testing positive at the border ... that's when we need to see some criteria around ... suspending travel for example."
He said the situation in India is "alarming" and Covid-19 cases have almost tripled since the travel suspension was announced. "It seems difficult at the moment to allow travel from India to resume," he said
But is a system that effectively bans New Zealanders from returning home work legal?
University of Otago law professor Andrew Geddis told RNZ there's no doubt the Government has power to ban New Zealanders returning under Covid-19 legislation passed last year.
"They can basically do anything they want to stop Covid-19 circulating through the country.
"The problem is the Bill of Rights Act contains a right for the right of New Zealanders to return to New Zealand."
The Covid-19 legislation can't be used if it is inconsistent with the Bill of Rights Act, he said.
"It has to show that there's enough of a risk of a threat to justify limiting those rights under the Bill of Rights Act and that's a very difficult calculus to work out."
The Human Rights Commissioner asked the Government for a clearer justification on the decision, and said banning New Zealanders from returning home is a significant limitation on their freedom of movement.
Technically the ban of people coming from India is open-ended, "it doesn't expire in two weeks", he said.
"If you look at the absolute numbers, the number of cases from India is about the same as the United States at its peak," he said.
But a much higher portion of people from India are travelling to New Zealand while sick than people from the US did, he said.