WA's COVID-19 cases have surged with the State recording 257 new local and five travel-related infections.
Today's new cases brings the total number of active COVID cases to 877, none of which are in hospital.
It comes after Premier Mark McGowan announced WA's border will reopen on March 3 allowing quarantine-free travel between states.
Travellers must be triple dose vaccinated, if eligible, have a registered G2G Pass and take a rapid antigen test on arrival.
Several new restrictions will also be introduced from 6am Monday, February 21.
Mask rules will be expanded State-wide in all public indoor settings, home gatherings will be restricted to 30 people and private outdoor gatherings (not at a private residence) will be limited to 200 people.
The two square metre rule will also be introduced for hospitality, fitness venues, entertainment venues, cultural venues, places of worship, hairdressers and beauty services.
"Introducing these public health measures is not something we want to do, but we know from the Eastern States' experience that applying measures before the peak will help in the long run," Mr McGowan said.
"Omicron is in our community, it is spreading through our workplaces, schools and social settings, and we know cases will jump significantly in the days ahead.
"Based on the latest health advice, we've had to make the difficult decision to introduce these measures in order to try to minimise the overall impact of Omicron and keep WA safe."
Anyone in the Perth, Peel, Wheatbelt, Pilbara and South West regions are being urged to get tested immediately if they are experiencing symptoms, even if they have not visited an exposure site.
Motorcycle passenger in critical condition after rider allegedly runs red light in East Rockingham
Two men charged over Australind murder
Last call for donations to support Mandurah's homeless
State Government commits to building $5 million electrical training facility at Rockingham TAFE
McDonald's approved for Dawesville
Wanted man known to frequent Kwinana, Mandurah and Rockingham areas
Mandurah woman completes grueling English Channel swim
Man and child seriously injured in South West crash
Motorists warned to expect delays during Kwinana Freeway upgrades