Japan's transport ministry has asked each air carrier to submit data every day on bookings for inbound international flights as the country steps up efforts to keep out the Omicron coronavirus variant, sources with knowledge of the situation said Saturday.

The request for updated information including the number of reservations for each Japan-bound flight was made after the government lowered this month its daily cap for people arriving from overseas to 3,500 from 5,000.

Travelers install a contact-tracing app in the quarantine area upon their arrival at Narita airport near Tokyo on Nov. 29, 2021, amid growing concern about the Omicron variant of the coronavirus. (Kyodo) ==Kyodo

Until recently, the ministry had asked airlines operating international flights to submit such data once a week. It is now asking them to do so daily until Jan. 31, according to the sources.

With the emergence of the new variant, Japan has in principle banned all new entries by foreigners from around the world.

But Japan has allowed a limited number of Japanese citizens and foreign residents to re-enter the country, using the daily ceiling.

The ministry's recent call for airlines to stop taking reservations for Japan-bound flights by the end of December caused confusion and an outcry from people who were planning to return home for the New Year holiday.

The ministry was forced to retract the blanket request on Thursday and said that reservations would be allowed within the government's daily cap of 3,500.

It is hoping to use the daily data to better track reservations by people willing to return to Japan and overall travel demand, the sources said.

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