New Zealanders and Australians rushed to book flights Tuesday as the beleaguered tourism industry welcomed the "lifeline" of a travel bubble between the largely coronavirus-free neighbours.

New Zealand Prime Minister Jacinda Ardern announced the two-way, quarantine-free travel corridor would open from 11:59 p.m. on April 18.

Jim Boult, the mayor of New Zealand's Queenstown, called the move a "saviour for businesses".

"This is the lifeline we needed; this is what we've been asking for," he said.

Air New Zealand and Qantas announced they were ramping up flights as thousands of tickets were sold immediately after Ardern's announcement.

A spokesman for Australian flag carrier Qantas said tickets to New Zealand were "selling like hot cakes" with a strong "load" to Queenstown, which is billed as the country's "Adventure capital".

Air New Zealand boss Greg Foran said his staff were "rushed off our feet".

The travel bubble comes more than a year after New Zealand closed its doors in response to the pandemic and six months after Australia allowed Kiwis to fly into selected states without the need to quarantine.

Before Covid-19 brought New Zealand's tourism industry to its knees, it was the country's biggest export industry, with Australians accounting for about 40 percent of the international visitors and contributing more than NZ$2 billion (US$1.4 billion) to the economy.

Tourism New Zealand boss Rene de Monchy estimated the opening of a travel bubble could recoup more than NZ$1.0 billion this year.

The trans-Tasman route is also Australia’s busiest international aviation market with travellers from New Zealand accounting for 18 percent of all air arrivals and spending A$1.6 billion (US$1.2 billion) annually on travel and tourism.

Ardern described the travel bubble as a world-leading move between New Zealand, with just 26 Covid-19 deaths in a population of five million, and Australia with fewer than 1,000 deaths in a population of 25 million.

"I cannot see or point to any countries in the world that are maintaining a strategy of keeping their countries Covid-free whilst opening up international travel between each other," she said.

"That means in a way we are world leading."

Australia Prime Minister Scott Morrison said he appreciates the arrangement.

"We welcome them back as indeed Kiwis will be welcoming Aussies," he said.

Last week, the tiny Pacific island nation of Palau, one of the few countries never to have had a Covid-19 case, opened a travel bubble with virus-free Taiwan. Palau President Surangel Whipps described the decision as a "ray of light" showing the world was slowly emerging from the pandemic.

Just hours before Ardern's announcement, British Prime Minister Boris Johnson said it would be at least another month before he could allow holidays abroad.

'Bring your family'

Ardern urged Australians to take advantage of the bubble, with New Zealand's ski season on the horizon.

"We are a safe place to bring your family to come and visit," she said during a press conference.

One of the hurdles in setting up the two-way corridor has been sporadic outbreaks of community transmission in both countries, with Australia repeatedly suspending quarantine-free travel from New Zealand due to virus outbreaks in Auckland.

The flare-ups have been successfully contained with snap lockdowns and Ardern said travellers needed to be aware that further outbreaks in either country could impact travel plans.

"People will need to plan for the possibility of having travel disrupted," she said.

"Just as we had alert-level settings for managing cases in New Zealand, we will have a framework for managing an outbreak in Australia," she said.

"In many ways, we will treat Australia as a region of our own when we're making decisions on restrictions."