Western Australia had no new community coronavirus cases on Monday, as residents of Perth and Peel waited to see if their three-day lockdown would end at midnight as planned.

Federal Health Minister Greg Hunt confirmed there hadn’t been a locally acquired COVID case anywhere in Australia in the 24 hours to Monday afternoon.

It came as WA Premier Mark McGowan was expected to step up for a media briefing on the lockdown plans at 12.30pm (WA time).

Earlier, he said Perth would be subject to extended COVID-19 restrictions past its initial snap lockdown, imposed on Friday after two virus infections emerged in the city.

“I’m sure there will be some further measures that continue,” Mr McGowan said on Sunday.

“What they are, we won’t know until tomorrow morning. We’ll get health advice … and I think people should get used to the prospect that there will be some further measures continue beyond Monday.”

Mr McGowan was expecting there to have been more than Saturday’s 12,000 COVID tests completed on Sunday, which would help health officials determine the path forward.

“If there’s further cases, what we do will be more than perhaps there is now. It all depends on the circumstances. I can’t predict what will happen. There will be an extension of some form of controls.”

Mark McGowan is expected to provide an official update on the WA lockdown later on Monday.

On Sunday, WA had two new coronavirus cases among returned overseas travellers in hotel quarantine. There were no further community-transmission diagnoses.

The lockdown was sparked by two ‘local’ transmission cases that have been traced back to a Perth Mercure Hotel used for quarantine. One was a Victorian man who tested positive for the virus after returning to Melbourne; the other case was a friend of his with whom he stayed in Perth for several days after completing quarantine.

Late on Sunday, authorities continued to search for and test hundreds of close and casual contacts of the confirmed cases.

A man aged in his 40s tested positive on Saturday after dining at a restaurant along with the two other confirmed cases. His household contacts have been cleared of the virus, but authorities have extended the list of possible transmission sites, including a childcare centre, based on his recent activities.

• See the latest list of exposure sites here

Mr McGowan remains locked in a verbal battle with the federal government over management of the states’ quarantine schemes.

He wants Canberra to open air bases and Christmas Island to accommodate the travellers, adding that it’s the Commonwealth’s constitutional responsibility to handle the quarantine scheme.

Australian Medical Association president Omar Khorshid said he believed the lockdown would continue after Monday night’s scheduled end, as “it will be a little more time before we’re absolutely certain we’re in the clear”.

“If there is something to be upset about, [it’s the] failure again of hotel quarantine,” Dr Khorshid told the Nine Network’s Today program.

“These facilities are not built for these purposes, they’re not perfect.

“We agree with Premier McGowan [that] more specific facilities should be made available.”

The AMA’s state president, Andrew Miller, went further, saying innocent people who were arriving without the virus were being infected in quarantine.

Dr Miller described the system as an abuse of human rights.

“The issue is that hotel quarantine isn’t fit for purpose,” he told ABC radio on Monday.

Dr Miller said federal experts were being “grossly negligent” and urgent change was needed.

“Hotels cannot be made safe for COVID-19 positive people,” he said.

“Governments need to put money into building mining camps – I’m told it can be done within a couple of months.

“And put everyone into N95 masks tomorrow. It’s all low-hanging fruit, frankly.”

However, Defence Minister Peter Dutton has said the Commonwealth facilities are not suitable and that the states previously agreed to manage the quarantine scheme.

The federal government has agreed to a halving of international arrivals into WA, down to 512 a week, until the end of May.

-with AAP