Sydney sees highest caseload in months despite lockdown

The city in the state of New South Wales reported 38 cases on Thursday - taking its outbreak of the Delta variant to about 370 cases, the BBC reported.

Authorities say household visits and meet-ups between friends were still driving the virus' spread.

They have pleaded with residents to follow the rules more strictly.

"We just need people to stop interacting for this lockdown to work," NSW Premier Gladys Berejiklian said on Thursday, which saw the highest figures in a day in the last 14 months.

"Please stop visiting people indoors, outside your family, your household. Your immediate family means those you live with, it doesn't mean extended family or friends," she said.

She added that people with symptoms moving around the community were also fuelling the virus' spread.

Australia's biggest city, home to five million people, is under a stay-at-home order until 17 July. The neighbouring Blue Mountains, Central Coast, Wollongong, and Shoalhaven regions are also affected.

Under the direction, people are allowed to leave their homes for essential reasons like shopping, exercise and care-giving. Businesses such as restaurants offering takeaway and many retail shops remain open.

Earlier this week, authorities were forced to extended the lockdown by a week based on the continued trend in case numbers - at around 18-35 new infections per day over the past week.

While a majority are being found in household contacts of infected people already in isolation - there are still a concerning number in those moving freely in the community.

"Those numbers are too high. We need to get those numbers down," said Berejiklian.

"We don't want to prolong the lockdown, we don't want to see Sydney going in and out of lockdown until we have the vast majority of our population vaccinated. It is up to all of us to step up, as difficult as it is."

Sydney's Delta outbreak and scares in other cities last week has sparked public anger over the federal government's slow vaccine rollout.