"The consequences of it are no more severe than any other strains of Covid-19. You could see similar symptoms, similar effects, and the vaccine would still work," he said.
"The extra PCR test will be applied on 'day zero', as returnees who've been in the United Kingdom or the United States during the preceding 14 days go through New Zealand airport controls, or on 'day one', after they arrive at a managed isolation and quarantine facility."
The majority of cases originally come to New Zealand from either the UK or US, the next tier down are countries like India, Pakistan and Mexico.
The new testing will be in addition to the current day-three and day-12 tests.
"The returnees will also be required to be in isolation or quarantine in their allocated room at a facility until their initial test has returned a result," Hipkins said.
"This means if the result is positive they will be transferred to a quarantine facility effectively several days earlier than under the standard two-test regime.
"We've been monitoring overseas developments very closely, and, like many other countries, New Zealand has heightened concerns about the new variants of the virus and their potential to spread more rapidly, and the ongoing high rates of infection in some countries.
"We're seeing asymptomatic people coming across the border who are subsequently picked up in day-three testing, so this will pick them up as early as possible.
"It will also help us identify earlier anyone who sat close to them on flights."
Hipkins said while growing travel restrictions were being imposed in countries that host airport hubs and by airlines themselves – which block routes to New Zealand for the overwhelming majority of travellers from higher-risk countries – the Government was taking this extra precautionary step to "provide another layer of protection and to support our goal of making summer unstoppable".
He said the additional requirements would provide extra safety for those working in MIQ facilities, and the public.
Hipkins also announced there would be pre-departure testing for UK arrivals to New Zealand from mid-January.
"Keeping the virus out remains our biggest protection and as we've done all along, we regularly review our settings and make changes where they will make a difference," he explained.
"Plans for pre-departure risk-reduction measures, including testing for people leaving the United Kingdom for New Zealand, are currently being worked on, with a view to implementing them from mid-January.
"These include selecting the most effective forms of testing in the circumstances. Additional risk measures for other countries are also being considered.
"Returnees will still need to go through our 14-day managed isolation and quarantine process, on arrival in New Zealand."
He acknowledged the further process "would present an extra hurdle for Kiwis planning to return".
"We're not considering this lightly," he said.
"We're going beyond what we've done in the past, to stay ahead of what appears to be a worsening situation globally and, in doing so, we would reduce the risk of Covid-19 spreading during transit and entering our managed isolation facilities."
Hipkins said an "eventual safe travel zone" with Australia and realm countries would ultimately mean fewer people from lower-risk countries staying in New Zealand's managed isolation facilities.
That would then allow more people from higher-risk countries to arrive.
"Additional offshore risk measures including pre-departure testing would help us prepare for the increased risk such arrivals will bring to our facilities and to incoming flights," he said.
As of yesterday, there were 16 new cases of Covid-19 in New Zealand recorded since Christmas Eve.
Fifteen of the cases are at the border.
The other was a historical case in the community from seven months ago which has now been confirmed.
The total number of active cases in New Zealand is 50 after 15 cases recovered.
Our total number of confirmed cases is 1788.
