FREDERICTON -- Most of Canada's Atlantic provinces reported a surge in COVID-19 cases on Saturday, with New Brunswick setting a new single-day record for new diagnoses in the province.

Dr. Jennifer Russell, the province's chief medical officer of health, said the 23 new cases that surfaced in the past 24 hours mark the largest one-day increase since the pandemic was first declared in March.

New Brunswick now has 71 active cases, with one person in hospital.

"We are facing a serious situation with the renewed transmission of the virus in New Brunswick," Russell said. "We need a renewed commitment to slowing the spread of COVID-19, and we need it now."

Sixteen of the province's latest cases are in the Saint John health region, six are in and around Moncton and one is in the Fredericton area, Russell said. Both the Saint John and Moncton regions are under heightened public health restrictions, which include single-household bubbles and limited travel into and out of the areas.

Nova Scotia, meanwhile, announced eight new cases of COVID-19 two days before parts of the province prepare to face tighter public health restrictions.

"This is the single largest jump in COVID-19 cases we have seen in our province in recent months," Chief Medical Officer of Health Dr. Robert Strang said in a release outlining Saturday's numbers.

The province said two of the most recent cases are connected to previously identified patients, while the source of the remaining six cases are under investigation. There are now 33 active infections in Nova Scotia.

Residents of Halifax and parts of Hants County will be facing stricter public health protocols effective Monday as the province imposes new rules. Gatherings in those areas will be capped at five people when physical distancing measures can't be maintained.

Case numbers surged slightly in Newfoundland and Labrador as well on Saturday, with provincial officials saying the five new infections recorded over the past 24 hours marked the largest single-day spike seen since early April. The new patients include a man over 70 who is a resident of a retirement facility in the small town of Grand Bank, N.L., on the Burin Peninsula. His is the sixth case reported in the town in the past week, but provincial officials said all six cases are connected.

Public health officials said they were still investigating the source of an infection announced Friday in the western region of the province.

Newfoundland and Labrador now has 18 active cases of COVID-19 with one person in hospital.

Provincial officials also altered their advice for residents visiting Nova Scotia a day after identifying a case linked to travel in that province. Officials issued a release asking travelers to limit their close contacts while they're there and to monitor for symptoms of COVID-19 for two weeks after they arrive back home.

Newfoundland and Labrador and Nova Scotia are part of the so-called Atlantic bubble, which permits residents of Canada's eastern provinces to travel freely between them without having to self-isolate for 14 days. That travel is still allowed, said Saturday's release, and the request for extra vigilance is made "out of an abundance of caution."

Officials in New Brunswick issued a similar advisory hours later, suggesting those who visited the Halifax area may be at greater risk due to community transmission in the city. Travelers are being urged to self-monitor for symptoms upon their return to New Brunswick.

This report by The Canadian Press was first published Nov. 21, 2020.

With files from CTV Atlantic's Heidi Petracek