SYDNEY: Australia's prime minister on Wednesday blamed restricted vaccine supply from Europe for his country's halting coronavirus inoculation efforts, as he faced down growing public frustration over the sluggish rollout.

Scott Morrison said vaccine shortages and "strict export controls" introduced by the European Commission meant Australia received just 700,000 of a contracted 3.8 million doses of the Oxford/AstraZeneca vaccine.

His government, which received global praise for successfully containing Australia's coronavirus outbreak, has fallen far behind its schedule for vaccinating people.

It had initially pledged to administer four million doses by the end of March, but had instead managed about 850,000 shots by Wednesday -- drawing increasing criticism that Morrison tried to address at a hastily organised press conference.

"I'm simply explaining to the Australian public that supply issues is what's constraining and has constrained, particularly over the recent months, the overall rollout of the vaccine," he said.

"3.1 million vaccines didn't arrive in Australia -- that's just a simple fact," he said.

"It's not a dispute. It's not a conflict. It's not an argument. It's not a clash. It's just a simple fact."

Australia has reportedly received a million doses of the Pfizer/BioNTech vaccine, which it is administering to frontline workers.

But authorities had been counting on imported and locally made AstraZeneca shots to cover most of the population.

Trouble surfaced last month when Italy blocked the export of 250,000 AstraZeneca doses as it struggled to cope with a severe coronavirus crisis at home.

Morrison's government said at the time the Italy move would not affect its overall vaccine rollout plan.