Southeast Queensland is "on the verge" of a lockdown after recording two new local cases of COVID-19, with the government mandating the wearing of face masks.
Premier Annastacia Palaszczuk says one new case is believed to the Alpha strain and linked to a cluster involving the Portuguese Family Centre in Brisbane.
The other is a case of the Delta strain, a close contact of a miner who was out in the Sunshine Coast town of Bli Bli after becoming infected at a Northern Territory mine.
Chief Health Officer Jeannette Young is more concerned about 169 other workers who arrived in the state from the same mine and are still being tested.
She's also on alert about passengers exposed to an infected crew member on flights from Sydney that arrived in Brisbane and the Gold Coast over the weekend.
Ms Palaszczuk has moved to mandate mask use indoors and outdoors across 11 local government areas.
"We are on the verge (of a lockdown), but we are monitoring very, very closely over the next 24 to 48 hours (whether) will we see any further community outbreaks in Queensland," Ms Palaszczuk told reporters.
"This is the Delta strain, you've seen how quickly it has escalated NSW over a period of about 10 days.
"So we're looking at this day by day and we will not hesitate to take action."
Residents of Brisbane, Ipswich, Logan City, Moreton Bay, Redlands, Sunshine Coast, Noosa, Somerset, Lockyer Valley, Scenic Rim and the Gold Coast have to wear masks for 14 days as of 1am Tuesday.
Face masks must be worn at all times outside the home unless eating, drinking or exercising.
Dr Young urged people in the southeast not to wait until the mask mandate formally comes in on Tuesday.
She said any person who leaves those 11 local government areas will have to continue wearing masks while they do.
"So we've got an enormous risk throughout our state, but I'm very confident with all our strategies and our mitigating factors that we have in place, and everything that all of us have learned over the last 18 months, that we can manage this," Dr Young said.
"So please, everyone's getting really good at wearing masks, please put them back on."
The state government has foreshadowed an extension of the mask mandate to other LGAs.
Other restrictions have also been tightened with a maximum of 30 people including children allowed to visit homes.
Wedding and funerals will be restricted to 100 people with only 20 people allowed to dance at the former.
There will be a one person per four square metre rule in venues and no dancing will be allowed at all.
Ticketed or fully seated venues with COVID-19 plans will be allowed to continue operating at full capacity
Queensland Chief Health Officer Jeannette Young is seen during a press conference in Brisbane. Source: AAP
"If we start seeing any spread of community transmission in NSW, especially closer to our border, we will not hesitate to take strong action," she said.
NSW recorded 18 new local COVID-19 cases on Monday, with all but one linked to known infections as residents across Greater Sydney endured their second full day of lockdown.
QLD Opposition Leader David Crisafulli called on the government to offer lump lockdown payments, and deep cleaning and event cancellation rebates to small businesses in the event of a lockdown.
"They've been to hell and back in the last 18 months, and this would be a major shot in the arm for confidence," he said.
Queensland will call for its overseas arrivals cap to be cut to free up space in hotel quarantine for residents returning from interstate amid the multiple outbreaks across Australia.
Deputy Premier Steven Miles said if the federal government had approved the state's proposed quarantine facility near Toowoomba the current situation could have been avoided.
"We wouldn't be reducing our number of international arrivals if we had purpose-built facilities which would, could have been up and running now," he said.
The state recorded one new virus case in hotel quarantine on Monday morning.