Australia Prime Minister Scott Morrison claimed around 80 percent of Australian coronavirus cases came from those who caught disease overseas or were in contact with someone who returned from abroad.

"The overwhelming proportion of cases in Australia have been imported," Morrison told a news conference on Friday. While in an interview with 2GB on the same day, he gave further details by claiming that the U.S. is the country of origin for most of the coronavirus cases in Australia.

"The country which has actually been responsible for a large amount of these (coronavirus cases) has actually been the United States," the prime minister said, attributing the large amount of import to U.S.' failure of conducting adequate numbers of tests, which suggested that the U.S. may have many more infections in recent weeks than had been announced.

"I don't think there's any suggestion that any country, including China, has done anything deliberately," Morrison was quoted as saying.

Report from Australian Department of Health revealed that a third of the infections were traced back to travelers from the U.S.

As of Sunday, Australia has 1,286 confirmed cases of coronavirus, with the total doubling roughly every three days, according to the department.

Morrison government earlier estimated that up to 150,000 Australians could die from the coronavirus under a worst case scenario.

Earlier this week, Morrison announced a ban on nonessential gatherings of 100 or more people in the country, but exempted schools, universities, shops, health services and public transport.

It closed its border on Friday to foreigners exempting Australian citizens and permanent residents in a bid to contain coronavirus.

(Cover: Australian Prime Minister Scott Morrison speaks during a joint press conference with New Zealand Prime Minister Jacinda Ardern at Admiralty House in Sydney, Australia, February 28, 2020. /Reuters)