Ms Stephen-Smith urged people to observe social distancing guidelines and stay away from groups of people, amid reports of crowding at shopping centres on the weekend.

Police also reportedly broke up sporting games on playing fields.

It came after the ACT lifted some restrictions on Saturday, allowing private indoor and outdoor gathers of up to 10 people.

"Please remember that it only takes one person with COVID-19 undetected in the community, who goes into a crowded space and comes into contact with multiple other people to start a new cluster," she said.

The ACT on Monday recorded a week without any new coronavirus infections. But Ms Stephen-Smith said the impact of the eased restrictions - and whether they lead to a spike in cases - would not be known for weeks.

ACT chief health officer Dr Kerryn Coleman said it was "a shame" to hear people visiting reopened shops over the weekend were not complying with the requirements.

"Failing to adhere to physical distancing and social gathering requirements could undermine all of this work very quickly," she said.

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