Queensland will permit those living in Adelaide to travel unrestricted into the state from 1am on Saturday 12 December.
The reopening of the QLD border to Adelaide is conditional on the South Australian capital recording no new unlinked cases of COVID-19 before Saturday.
QLD health authorities say the reopening is possible because by Saturday it will have been 28 days since the first case was recorded in connection to the Parafield cluster in Adelaide.
With that outbreak now under control, Queensland it set to welcome those in SA back to the sunshine state for Christmas.
The news comes as Western Australia confirmed it will be reopening its border to residents from New South Wales and Victoria.
That reopening occurred overnight, with those in NSW and VIC now able to cross into WA without having to complete 14 days of self-quarantine on arrival.
It brings the two states in line with other jurisdictions already classified as "very low risk", including the Australian Capital Territory, Queensland, Tasmania and the Northern Territory.
Queensland reported three new cases of COVID-19 yesterday, all returned overseas travellers in hotel quarantine.
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