Australia will evacuate over 200 citizens on board the coronavirus-hit Diamond Princess cruise ship docked in Yokohama, Prime Minister Scott Morrison said Monday.

Passengers, many of whom have been described as "quite elderly," will depart on a chartered flight to Darwin in northern Australia on Wednesday, where they will be required to spend a further 14 days in quarantine.

Morrison said the extra two weeks of quarantine will be required because the nature of the quarantine measures aboard the Diamond Princess cannot be assured.

"I understand that those who were on board will feel very frustrated about this, as well as their family members," he said. "But our first responsibility is that we have to protect the health and safety of Australians in Australia today."

To date, 15 Australians have tested positive for the new coronavirus, with no cases of secondary infections detected.

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