Japan is considering requiring all inbound travelers to undergo a test for new variants of the coronavirus, health minister Norihisa Tamura said Sunday.

Under the current system, all people arriving from 24 designated countries where coronavirus variants are known to exist are required to take additional testing three days after entering Japan. Authorities also carefully monitor whether they are strictly observing a 14-day self-quarantine period.

An arrival lobby for international flights is seen deserted at Kansai airport in Osaka Prefecture on Jan. 5, 2021, amid the novel coronavirus pandemic. (Kyodo)

While speaking of the need to tighten border controls on an NHK television program, Tamura also said the government is considering contracting private security companies to monitor those who should be self-quarantining at their accommodation to make sure they adhere to the rules.

On Saturday, Japan tightened border controls on travelers from seven additional countries, mainly from Europe.

Japanese and other nationals who have recently traveled through Estonia, the Czech Republic, Pakistan, Hungary, Poland, Luxembourg and Lebanon fall under the scope of the system.

As the government has decided to end the COVID-19 state of emergency in the Tokyo region on Sunday, the minister also said, "It is important to avoid activities with a high risk of infections."

Prime Minister Yoshihide Suga formally announced Thursday the lifting of the emergency in Tokyo and neighboring Kanagawa, Chiba and Saitama, the last prefectures of Japan under the measure since early January.

Under the measure, people were urged to refrain from nonessential outings and restaurants and bars told to close by 8 p.m.

On the same TV program, Shigeru Omi, head of the government's COVID-19 subcommittee, warned that "a rebound in infections is possible to occur in the next one or two months."

Omi said it is vital to prevent the further spread of the virus until people aged 65 or older in Japan are being vaccinated, with that group eligible to start receiving shots in mid-April.

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