MELBOURNE, AUGUST 01

Australia's east coast states of New South Wales and Queensland faced an escalating battle against the COVID-19 Delta variant on Sunday, with millions under strict lockdown and authorities urging more testing and vaccinations to rein in the outbreaks.

Sydney and its surroundings, under a stay-at-home order for five weeks already, reported 239 new locally acquired cases of the highly infectious Delta strain, matching the record daily number in the current outbreak that was reported on Thursday.

The city's 5 million residents and those in neighbouring regional centres spanning 200 km (120 miles) of coastline are to stay home until Aug. 28 at least. The total number of cases in the outbreak, which began in mid-June, has reached 3,427.

'I think what is important to know is that there is no roadmap for the Delta variant,' NSW Premier Gladys Berejiklian said.

'The challenge for us is getting as many people vaccinated in August as possible so by the time 28 of August comes around, we have options as to how we can ease restrictions.'

Australia's vaccination drive has been sluggish, with only 18% of adults fully vaccinated so far. Brad Hazzard, NSW health minister, said that 70% of the state's population could be fully vaccinated in about four months.

In neighbouring Queensland, there were nine new locally acquired cases of COVID-19, the biggest daily spike in almost a year. More than 3 million residents were put into a three-day snap lockdown on Saturday.

'It is vital (to get tested), anyone with any symptoms at all, it doesn't matter where you are, because I don't know where this virus is at the moment,' Queensland's chief health officer Jeannette Young said.

Australia has managed to keep its epidemic largely under control with a total of just over 34,000 cases and 924 deaths. But the slow vaccination drive means that it could be months before the country's borders reopen.