South Koreans aboard a coronavirus-stricken cruise ship off the coast of Japan will face an additional two-week quarantine period back in Korea, if they wish to return, according to public health authorities on Monday.

Earlier on Sunday, Seoul announced it would repatriate Korean passengers and crew members from the Diamond Princess ship being held under quarantine at the Yokohama port, where 355 cases of the COVID-19 virus have been confirmed, in the largest cluster of virus cases outside of China.

There are 14 Koreans onboard -- nine passengers and five crew members, all of whom are reported as unaffected. They have been held inside the ship with around 3,700 people since Feb. 3, after a former passenger was diagnosed with the virus.

The mandatory quarantine is set to end Wednesday, and those who test negative may leave the ship then. But with the number of infected rising rapidly inside the vessel, many countries are speeding up the evacuation mission.

“If the passengers and crew members wish to return and consultation with Japanese authorities goes smoothly, they can return to Korea. Through the diplomatic offices in the region, we are checking their intention to return,” said Kim Kang-lip, vice health minister, in a regular briefing Monday. “We think there is considerable danger, thus find it necessary to impose 14-day quarantine at an isolated place, following similar action taken against South Korean citizens evacuated from Wuhan, China.”

Seoul previously sent three chartered planes to repatriate people living in Wuhan, the epicenter of the COVID-19 virus outbreak, with all required to stay in public quarantine facilities for two weeks after arrival.

As to the exact time period and method of repatriation, the government is still sorting out details, according to a Foreign Ministry official on condition of anonymity. “We are still checking the intention of the citizens whether they want to return,” he said, adding Japanese authorities have been cooperative with Seoul’s plan.

On speculation that the government will use military aircraft for evacuation, Seoul’s Defense Ministry said it has not reviewed the matter yet.

Early Monday morning, the US began the evacuation of some 340 Americans leaving the cruise on a US charted flight home. Once they arrived in the US, they were to be quarantined for 14 days.

Some 40 Americans who are infected on the cruise were not part of the evacuation, as they will stay in Japan for treatment.

Canada, Italy, Australia and Hong Kong are now planning to send planes soon to repatriate their citizens from the cruise.

As of Monday, more than 71,700 have been infected with COVID-19 around the world, with the death toll reaching 1,775, mostly in China.

By Ahn Sung-mi (sahn@heraldcorp.com)