More West Australians will be required to wear face masks as Omicron infections rise and the state prepares to soften its hard border rules.
WA has recorded 85 new local COVID-19 cases over the past five days as clusters emerge throughout Perth and the state's south.
Ten new local cases were reported on Thursday but just 5635 tests had been carried out on the Australia Day public holiday.
From 6pm on Thursday, people in the Wheatbelt and Great Southern regions will be required to wear masks at all indoor public settings.
The face coverings are already mandatory in Perth, Peel and the South West.
"What we are seeing with cases in regional WA is concerning," Premier Mark McGowan said.
"We know how quickly Omicron spreads, and we know it doesn't respect regional boundaries."
The spike in cases threatens to render WA's indefinite border closures redundant, with the premier conceding the state has no chance of eliminating its Omicron wave as it did previous outbreaks.
A broadening of exemptions for entering WA will come into effect from February 5, the date which had previously been flagged for removing border controls.
The list includes people with direct family connections in WA and locals returning from visiting relatives in the eastern states.
Other people who have lived in WA within the past two years will be allowed back if they permanently relocate, as will some students and skilled workers.
All arrivals still face 14 days in quarantine, including those allowed to return for funerals, to undergo urgent medical treatment or to see dying relatives.
Domestic arrivals can self-isolate if they have suitable premises, while direct international arrivals must spend at least a week in hotel quarantine.
But the government has confirmed returned overseas travellers can bypass hotel quarantine if they fly into WA from another state.
The arrangement has been panned by the industry body representing international airlines in Australia.
The Board of Airline Representatives of Australia estimated there were about 20,000 West Australians overseas, with just 265 currently allowed to return each week through hotel quarantine.
"The recent announcement over home quarantine arrangements via entry into other states ... is difficult to understand," BARA executive director Barry Abrams said on Thursday.
"Why cannot the passengers simply fly direct into Western Australia and then home quarantine? And why have hotel quarantine at all then?"
The premier said WA had to keep its hotel quarantine system operational because once the borders reopened, there would be infected people with nowhere to isolate.
He said the hotels would be needed until at least July or August when the federal government's Bullsbrook quarantine hub opened.
Mr McGowan insisted his controversial decision to delay reopening the borders would buy valuable time for West Australians to get their boosters, with the third dose rate sitting just below 33 per cent.
"The lives of older Western Australians matter, as well as the immunocompromised and those with underlying conditions," he said.
Australian Associated Press