Canberrans will be able to travel freely to regional NSW and parts of Sydney and not need to quarantine on return after chief health officer Kerryn Coleman relaxed the ACT's border ban.
Restrictions on people from Central Coast and Wollongong were lifted at 3pm on Tuesday, leaving 11 local government areas in western Sydney and the northern beaches as coronavirus hotspots.
Non-ACT residents from the hotspot districts are banned from entering the capital without a valid exemption for at least another week, when Dr Coleman will revaluate Sydney's COVID-19 clusters.
Canberrans who had been in those areas in the past fortnight can come home but are required to quarantine for 14 days upon return.
ACT residents in isolation after returning from other parts of Sydney, Central Coast and Wollongong were given the all clear to leave quarantine on Tuesday afternoon.
Dr Coleman said the decision to relax the ACT's border ban came after the coronavirus outbreak in Sydney had "stabilised somewhat" in many parts of the city in the past week.
But she said parts of the city's west, south-west and northern beaches, where the outbreak started last month, still posed a risk to the ACT.
NSW reported five new cases of COVID-19 on Tuesday, including a person who presented to Mount Druitt hospital in Sydney's west on the weekend.
"While NSW continues to get on top of these cases, these areas still pose a high enough risk to the ACT to retain the existing travel and quarantine requirements for anyone coming from these areas," Dr Coleman said.
"We also urge people from these areas not to travel to the ACT at this time."
Dr Coleman said her team considered a number of factors before declaring the 11 districts as coronavirus hotspots, including case numbers, circumstances surrounding confirmed infections, the number of locations potentially exposed to the virus and local testing rates.
The decision came after the ACT removed its hotspot declaration for greater Brisbane on Monday, releasing about 4800 people who had visited the Queensland capital since early January from mandatory isolation.
Chief Minister Andrew Barr said the changes announced on Tuesday were a positive step, but was not a sign for Canberrans to "collectively drop our guard on the virus".
"Restrictions are only in place for the time necessary to reduce the risk to our community and to avoid community transmission and seeding of the virus," Mr Barr said.
"We wish to avoid COVID outbreaks, that's why those measures are put in place and why they will continue to be in place from time to time, affecting any part of Australia, often at short notice."
Mr Barr warned those travelling that outbreaks could pop up at any time and it could and would "result in travel restrictions, border closures and hotspot declarations."
"That is a fact of life in Australia in 2021," he said.
Police will continue to enforce the remaining border restrictions, Mr Barr said.
Dr Coleman said while there was no specific triggers for an area to be declared a hotspot, she was "more likely to want" to impose restrictions if cases popped up "out of the blue" and the source of infection could not be traced.
With the possibility restrictions could be brought in at short notice, Dr Coleman said Canberrans needed to consider the risks before travelling outside the ACT.
"[Travellers should] determine whether they will be able to survive quarantine period if something happens out of the ordinary happens in the future," she said.
"We will not be able to tell people straight forward and right down the line 'do not travel' or 'do travel to places not listed as COVID-19-affected areas'.
"Consider whether you really need to go."
When asked if the decision to allow more people in from NSW would increase the likelihood of more cases in the ACT, Dr Coleman said her decision was not a risk-free exercise.
She said it was about striking a balance.
"[It's] about balancing reducing the risk of seeding in the ACT, but also balancing this with the need for people to get on with their lives and conduct their everyday business," she said.