The Australian and New Zealand governments will receive a blueprint on safely reopening their shared international border as soon as next week.
A working group of officials and experts, including government personnel, airports and airline representatives, coordinated by the Australia New Zealand Leadership Forum, will produce the blueprint by "early June".
Co-chair of the group, Margy Osmond, said the goal was to provide the basis for the resumption of safe travel.
"We are poring over every detail and aspect," she said.
"We have an opportunity now to work together to show how we can support tourism on both sides of the Tasman and do it safely."
While the report will go to governments soon, neither Australia nor New Zealand is committing to a timeline on the re-establishment of regular travel.
Scott Morrison has pledged to "consider" the travel in July as part of the third and final step of his COVID-19 roadmap.
Jacinda Ardern is eager to move "as soon as it is safe to do so" and called the establishment of the bubble "a core plank in our economic recovery".
"Neither country wants to see cases imported from the other," Ms Ardern said.
On Wednesday, New Zealand recorded another day without new COVID-19 cases; just one case has been found in the past 10 days.
That has allowed Ms Ardern to relax gathering restrictions, with caps of 100 on all social engagements to come into force from Friday.
"We now have some of the loosest restrictions of the countries we compare ourselves to ... the opening of bars and restaurants," she said.
"What we're hoping to do is be free of almost all restrictions altogether within four weeks."
Australian deputy chief medical officer Paul Kelly said of the bubble, "it would be a wonderful thing for us to have that if it goes forward. I think it is certainly feasible to do so in the not too distant future".
Australian Associated Press