(Bloomberg) -- The delta-variant virus outbreak roiling Sydney is worsening as it spreads into regional areas of Australia, with several media outlets reporting Thursday that national capital Canberra is set to announce a snap lockdown after detecting at least one case.

New South Wales, Australia’s biggest state economy, recorded 345 new cases Thursday. Daily case numbers have generally been on a steady incline since the outbreak started in Australia’s largest city in mid-June; Sydney has been in lockdown for almost seven weeks, with Melbourne also enforcing stay-at-home orders.

Two more people in Sydney have died. Both were men in their 90s and had received at least one vaccine dose.

Three more local government areas of Sydney will face tighter social-distancing and movement restrictions, while the lockdown in the Hunter Valley region of the state -- including the city of Newcastle -- will be extended for at least another week, New South Wales Premier Gladys Berejiklian told reporters on Thursday.

With the nation’s two largest cities in lockdown as well as an increasing number of regional areas, the delta variant of the coronavirus is placing increased pressure on Australia’s so-called “Covid Zero” strategy, which has relied on closed international borders and rigorous testing to eliminate community transmission of the virus.

Prime Minister Scott Morrison is aiming to ramp up a tardy vaccine rollout in a bid to start reopening international borders next year, that have only been tightened over the course of the past year.

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