Australia must vaccinate 80% of its adults against COVID-19 before it can consider reopening its border, Prime Minister Scott Morrison said on Friday as he announced a four-stage plan to greater freedom.

Australia is now in phase A, or the suppression phase of the plan, with large parts of the country plunging in and out of lockdowns to stamp out the coronavirus.

Sydney is under a strict stay-at-home order because of a worrying surge of infections since the middle of June, driven by the highly contagious Delta variant.