It comes after a hotel quarantine security guard tested positive for the highly infectious UK strain of COVID-19 and spent several days in the community.

People in the Perth metropolitan area, Peel and the South West are not allowed to leave home unless shopping for essentials, for medical reasons, exercise or for work.

The advice initially stated that fly-in, fly-out workers would not be able to travel to and from lockdown areas.

The ruling would have left thousands stuck at work all week.

WA Police commissioner Chris Dawson later stepped in, declaring FIFO workers as essential and allowing them to travel to and from work.

"However, the WA government is requesting industry's co-operation to minimise any movement of workers over the next five days to only that which is absolutely necessary," the Association of Mining and Exploration Companies said in an email to members.

"AMEC encourages all members to support this request."

A look at the Perth Airport arrivals page showing close to half of regional flights had been cancelled or delayed.

WA premier Mark McGowan said today mining companies had been asked to minimise travel to essential workers only.

The Chamber of Minerals and Energy of WA is co-ordinating the industry's response.

"While the Police commissioner has defined resources sector workers as essential, the priority of CME and its members remains the health and safety of the wider community and the sector's workforce," CME CEO Paul Everingham said.

"As such, as responsible members of the WA community, we are keeping all outbound Perth travel to an absolute minimum."

Fortescue Metals Group CEO Elizabeth Gaines said the company's incident management team was meeting regularly to consider the latest guidelines.

"We anticipate receiving further updates from the government and WA Police later today," she said.

"While mining workers have been deemed an essential service, we support the need to minimise travel and have cancelled today's flights as we await updates on the situation. We are co-operating with the government to limit the movement of people during this important five-day lockdown.

"The health and safety of the Fortescue family is our highest priority and Fortescue will continue to work closely with authorities to ensure all relevant measures are implemented to reduce the likelihood of COVID-19 directly impacting our team, their families and the community."

Soon-to-be-merged gold producers Northern Star Resources and Saracen Mineral Holdings each put out statements this morning, with neither expecting any impact to production or exploration given all operations are outside the lockdown areas.