Premier Mark McGowan has urged NSW to toughen its COVID-19 measures to “kill” the virus, as he warned WA travellers to avoid the eastern state.

Mr McGowan has also indicated WA’s hard border with NSW may return before Christmas if the northern beaches outbreak worsens.

“NSW has had an outbreak. They need to find out why that happened … because that’s now having repercussions all over the country,” Mr McGowan told reporters on Friday.

“I think NSW should go to tougher measures. Both Victoria and South Australia showed how it was done.

“They took it incredibly seriously and they dealt with it and it looks like their measures worked.”

The Premier said while he was “sympathetic and supportive of our NSW brothers and sisters” the outbreak was debilitating for the country.

“The sooner NSW crushes it, the sooner they kill it, the better it is for them and the better it is for the entire country,” he said.

“What Victoria and South Australia showed is you can eliminate the virus … if you put in place the right measures.

“It’s far better than having it drift along and have these continual outbreaks.”

Mr McGowan said he was pleased to see NSW had taken on WA’s system of quarantining international aircrew in a dedicated hotel.

“I highly recommend this system,” he said.

NSW is now deemed a “low risk” state under WA’s controlled interstate border and travellers are required to self-quarantine.

Mr McGowan acknowledged many people’s plans had been thrown into disarray before Christmas, but said WA could not afford to take unnecessary risks.

“We are very concerned there will be many more community cases in NSW,” he said.

“There is no doubt NSW is on the verge of a serious outbreak and we must do whatever is required to keep us safe.”

The Premier said authorities would continue to monitor the situation in NSW extremely closely and do whatever was needed.

“This may well mean that the hard border with NSW needs to return in the near future,” he said.

“I will not hesitate to do that if that is what the health advice recommends, so can I ask all West Australians to avoid travelling to NSW.

“If you can avoid your travel to NSW, please do.”

Mr McGowan described it as a “fast-evolving situation” and “extremely fluid”.

“We’ve had to act extremely fast and do what is best to protect our state from a COVID-19 outbreak,” he said.

Despite one case being recorded in Queensland from the NSW cluster, Mr McGowan said he would not be making any further border changes at this stage.

Under WA’s border rules, travellers arriving from NSW must now self-quarantine for two weeks and be tested for the virus on day 11.

Those who arrived in WA between December 11 and 17, must self-quarantine and get tested as soon as possible, then return to self-quarantine until a negative test result is confirmed.

They must also have another test on day 11 after arriving in WA.

Almost 5000 people have arrived in WA from NSW since December 11.

That includes 616 people who came from other parts of Australia but had recently been in NSW.

Mr McGowan said 87 arrivals from the northern beaches had been contacted by contact tracers.

Almost 2000 people were tested for the virus on Thursday, including 522 at the airport.

COVID-19 clinics across Perth were inundated with people scrambling to get tested on Friday.

Many people arrived at clinics early in the morning after they were turned away on Thursday.

Some complained about the inconvenience of having to wait for hours, which has forced them to miss out on family Christmas events.

WA Health Minister Roger Cook said opening hours for clinics had been extended to meet demand.

WA recorded one new case of coronavirus overnight — a Turkish ship captain, who travelled to WA from Doha and is in hotel quarantine.

It brings WA’s total number of confirmed cases to 844.