Freight workers will be required to show proof of having returned a negative COVID-19 case in the past five days before being allowed to enter the state.
Mr McGowan acknowledged the change would put Christmas and reunion plans in disarray, but the situation in NSW had become “extremely concerning”.
“This is not what anyone wanted just days before Christmas,” Mr McGowan said.
“This has been a difficult decision to make given the time of the year.
“Right now I don’t know how long the border with NSW will be up for, we hope it’s only for a short period.
“All the way along our best offence has been our border control, right now we can’t take any unnecessary risks.”
Under previous restrictions rolled out on Thursday, travellers from NSW had to self-isolate upon arrival to WA and get tested for COVID-19 at one of the state’s clinic on day 11 of their quarantine.
Mr McGowan’s announcement comes after a coronavirus outbreak in NSW continues to grow with a cluster in Avalon hitting 41 cases on Saturday, sending Sydney’s northern beaches into lockdown.
On Saturday morning, NSW Premier Gladys Berejiklian asked the rest of Sydney to stay home as she flagged potential restrictions for the city’s broader area, depending on the day’s total case tally.
Other states also swung into action with Victoria deeming the northern beaches a “red zone” and forcing any residents who arrive from the hotspot to enter lockdown.
South Australia banned anyone who visited the Avalon Bowlo and Avalon RSL, the two venues at the epicentre of the cluster, from entering the state.
Speaking to the media on Saturday, WA Health Minister Roger Cook said the state would not be making any changes to its border arrangement at this time but cautioned the government would be forced to act if coronavirus cases in NSW exploded.
“I must stress that this situation could change and it could change at any time,” Mr Cook said.
Since December 11, 4901 people have arrived in WA from NSW. Of those, about 4500 have been tested for the virus in the state’s COVID-19 clinics. The number of patients swabbed across private pathology clinics is yet to be counted.
There are currently 68 residents from northern beaches in isolation in the state from 92 who initially travelled to Perth from the area.
They have all been tested for the virus and returned negative results.
Marta is an award-winning photographer and journalist with a focus on social justice issues and local government.