Northern Territory Chief Health Officer Dr Hugh Heggie declared the changes yesterday after a male hotel quarantine worker tested positive to COVID-19.

At 6pm last night, the WA hotspots entered a five-day lockdown.

Restaurants, cafes, pubs and bars will be providing takeaway service only, and the WA Government has asked that non-residents currently in Perth, Peel and the South West remain until the end of the lockdown.

Dr Heggie has cautioned that any person who has arrived in the Northern Territory between January 25 and January 31 from a declared hotspot in WA must have a COVID-19 test and undertake self-quarantine until a negative test is returned.

Anyone arriving from a hot spot after Dr Heggie's announcement will have to undertake quarantine at the Howard Springs facility for 14 days.

"There is the potential for the positive hotel quarantine case in WA to be a highly contagious mutant strain of the virus," Dr Heggie said.

"For this reason, we are taking swift action while we wait and see what happens in Western Australia over their lockdown period.

"We are taking all precautions and declaring Metropolitan Perth, the Peel Region and the South West Region of Western Australia as COVID-19 hotspots as part of our commitment to go hard and wide early."

Dr Heggie said he will be monitoring the WA situation closely, asserting "all appropriate actions to protect the health and safety of Territorians" will be taken.

"The decisions made in the coming days will be critical as public health controls are implemented and COVID-19 community testing is increased," he said.

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