The government is considering making private health insurance coverage compulsory for overseas visitors to next summer's postponed Tokyo Olympics, sources familiar with the plan said Friday.

The move, if put in place along with other measures, would be a step aimed at shaving Japanese public expenditure to treat visitors infected with the novel coronavirus.

Photo taken in January 2020 shows a monument depicting the Olympic rings in front of Tokyo's new National Stadium, the main venue for the Olympics and Paralympics. (Kyodo) ==Kyodo

A proposal presented at a meeting of the ruling Liberal Democratic Party called for a requirement that overseas visitors take out private insurance coverage on top of producing a negative test result for the virus, while also submitting a report on their health status and residence while in Japan.

Japan has classified the virus as a "designated infectious disease," meaning those infected can technically be treated for free, regardless of nationality.

Under current rules, the Japanese public bears virtually the entire financial burden of treating infected overseas visitors unless they are enrolled in Japanese public health insurance. That goes even for those with their own health insurance coverage.

For private health insurance to cover the treatment cost, either the virus needs to be reclassified or related laws must be amended, the sources said.

The issue of public expenditure surfaced after the mass infection aboard the Diamond Princess. About 700 people were infected while the cruise ship was docked in Yokohama and quarantined in February.

Koji Wada, professor at the International University of Health and Welfare who specializes in public hygiene, said public expenditures covered around 94 percent of the 288.43 million yen ($2.77 million) spent treating infected overseas visitors.

The government is mulling lifting the standard 14-day quarantine period for Tokyo Olympics visitors from countries and regions with low infections, while allowing them to use public transport. A decision will be made by next spring whether or not to even accept overseas visitors for the Olympics.

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