Premier Blaine Higgs says a review of the Atlantic bubble and travel rules may be in order if COVID-19 case numbers continue to worsen.
Higgs made the comments as numbers in both New Brunswick and Nova Scotia have increased in recent days.
While the bubble has been beneficial to both provinces, Higgs said there could be changes made in the future.
"And at this point, it would be a widespread community transmission that, you know, they really couldn't surround it and it really was [starting] to get out of control," said Higgs, when asked what it would take to make stricter controls at the borders necessary.
There are 24 active cases in Nova Scotia as of Wednesday morning, fewer than New Brunswick's active case count of 32.
But Dr. Robert Strang, Nova Scotia's chief medical officer of health, warned that community spread may be a factor in the province.
"There are seven cases where we can't identify a source that is directly related to travel," said Strang.
"We have to conclude this may be from local transmission."
While Higgs said the continuation of the bubble is not a given, he doesn't see an immediate need to re-establish checkpoints at the provincial border, but said it will be a topic at this week's COVID cabinet committee.
"We will be working with Public Health and we'll be having that discussion this week on how risky it is," said Higgs.
"I don't think we're ready to go back to a border between Nova Scotia and New Brunswick just yet."
Higgs said there may be a need for more restrictions on travel outside the Atlantic bubble.
Most people who travel outside the bubble must self-isolate for 14 days once they return to New Brunswick.
But there are exemptions for some who are working an essential job and some people who travel outside the bubble for work can do a modified quarantine where they can access some essential services while they await test results.
Higgs said some people appear to think this means they can move about freely, and if that attitude doesn't change, more restrictions may be on the way.
"Travelers can't come home and think it's two weeks of freedom," said Higgs.
"They've got to be very cognizant of where they're going, [that] they're fully protected and they're staying away from visiting people as normal. Because that is going to be our risk and it's going to be our downfall if it's not controlled."