New measures have been implemented for travellers entering the ACT from Western Australia after three new COVID-19 cases were recorded in the state.
Health authorities have warned Canberrans not to travel to WA in the wake of the new cases.
Those who have been in either Perth or the Peel region in the past 14 days will be required to complete an online declaration form within 24 hours of entering the ACT.
Those who have already completed a declaration form in the past two weeks don't need to fill out another one unless they were in Perth or the Peel region from April 27 onwards.
ACT health authorities have urged for anyone who has been in Western Australia to monitor for Covid symptoms.
"Given the evolving nature of the situation, travel to WA is discouraged at this time," an ACT Health spokesman said.
"If ACT residents do choose to travel to WA, they should be prepared for things to change quickly and to complete an online declaration form on return to the ACT.
"This situation is a reminder that COVID-19 is still with us."
The new travel alerts were sparked after a hotel quarantine security guard in Perth tested positive to COVID-19 on Saturday.
A further two cases were detected in housemates that lived with the security guard.
The housemates worked as food-delivery drivers, with a number of locations identified as public exposure sites.
No further cases of community transmission have been identified.
WA Premier Mark McGowan said on Sunday a lockdown was not needed, but said it was an option if the situation got worse.
The additional cases did, however, force a ban on crowds at the local derby AFL match between the Eagles and Dockers, which was set to play out before 45,000 fans at Optus Stadium on Sunday afternoon.
Perth and the Peel region had only just emerged from a three-day lockdown in late April after transmission of the virus leaked out of hotel quarantine.
