Officials have said that Australia is sticking to plans to start re-opening to the rest of the world only from the middle of next year and resisting mounting pressure to end the closure of international borders, Reuters reports.

"All the way through we will be guided by the medical advice," Prime Minister Scott Morrison said at a televised briefing. "We will be guided by the economic advice."

Earlier in the day, Treasurer Josh Frydenberg told the Australian Broadcasting Corp that the medical advice to keep the borders closed had "served us very well through this crisis".