The government plans to consider advice on mandatory mask-wearing at alert level two and higher, and mandatory QR code scanning at high-risk areas.

Speaking at a post-Cabinet media briefing this afternoon Prime Minister Jacinda Ardern says Cabinet has commissioned advice on making QR code scanning mandatory at some high-risk locations and would look to consider that advice next week.

She says the government would also consider mandating face mask use in regions that were at alert level 2 and higher. Mask wearing is already mandatory on public transport.

"The rise of the Delta variant and the risk is poses to the Trans-Tasman bubble means it's timely to consider new measures for our toolbox to strengthen the bubble and reduce the risk of Covid spreading in New Zealand," she says.

"In order to get and keep in front of the virus, we need to be able to contact trace quickly."

Ardern says the Covid-19-positive Sydney traveller who arrived in Wellington had made thorough use of the Covid-19 app, and that had been valuable in tracing his movements and quickly identifying places of interest.

However, while about 2600 people were estimated to have been at those places of interest, only 585 alerts were sent out to people who had used the NZ Covid Tracer app, she says, suggesting only a third of potential contacts of the case had used the scan into the locations of interest.

Cabinet also met yesterday and agreed to extend Wellington's alert level 2 status until 11.59pm tomorrow. The pause on quarantine-free travel was also extended to all of Australia and will last for the same duration.

Wellington shifted from alert level 1 to 2 last Wednesday after a Sydney man who visited the region between 18 and 21 June tested positive for the highly infectious Delta variant upon his return to Australia.

His partner has also since tested positive, while New South Wales' cases continue to climb.

The rest of New Zealand remains at alert level 1.

- RNZ