Perth locked down after first virus case in 10 months

The city of Perth has been locked down for five days after Western Australia state's first case of local COVID-19 infection in almost 10 months.

The city of 2 million people and coastal towns to the south have been locked down from Sunday night until Friday night.

The restrictions were put in place after a security guard who worked at a quarantined hotel contracted a highly contagious British variant of the virus.

Overseas travellers who arrive in Perth must isolate for 14 days.

All residents must stay at home unless shopping for essentials, attending to medical needs, exercising within their neighbourhood or working if unable to do so remotely.

Schools which were due to resume on Monday will remain closed for another week.

The last previous known case of someone being infected with COVID-19 within Western Australia was on April 11.

Western Australia, Australia's largest state by area, has remained virus-free for months by enforcing the nation's toughest border restrictions in an elimination strategy.

Those within the state have enjoyed some of Australia's least restrictive pandemic measures because of the low risk.