Western Australia is shutting its border to Victorian travellers again following an outbreak of COVID-19 in the eastern state.

From 12.01am on January 1, only exempt Victorian travellers will be allowed into WA, while returning residents will be required to self-isolate for two weeks and be tested on day 11.

“We don’t want them to get caught out, so they will be dealt with on a compassionate basis, case-by-case,” Acting Premier Roger Cook told reporters on Thursday.

The exemption list is limited to certain senior government officials, some active military personnel, federal parliamentarians, a person carrying out functions under Commonwealth law, people responsible for transport freight or logistics, and anyone who is granted approval.

Anyone who arrived in WA from Victoria on or after December 21 must also self-quarantine for 14 days and be tested on day 11.

“This is an evolving situation that is changing day by day, even hour by hour,” Mr Cook said.

“We are dealing with an unpredictable situation, which is likely to get worse before it gets better.

“The timing is terrible but COVID-19 doesn’t respect dates, it doesn’t respect celebrations.”

Mr Cook said the Health Department was preparing COVID-19 clinics for a surge in people presenting for tests but flagged there would likely be long lines.

He cautioned everyone planning to travel interstate to have flexible bookings during the pandemic because the situation could change quickly.

Police Commissioner Chris Dawson said since December 21 there had been more than 16,000 people arrive in WA from Victoria by air or road, including those arriving on one of the eight flights on Thursday.

WA has already shut its border to NSW travellers following an outbreak in that state. Both states are now deemed “medium risk”.

NSW recorded 10 new locally transmitted cases of the virus on the last day of the year, while Victoria recorded five.

WA recorded two new cases of coronavirus overnight, both overseas travellers who are in hotel quarantine.

It brings the state’s total number of confirmed infections to 861.