The government plans to require airlines to submit personal data on all passengers on departing and arriving flights as it ramps up counterterrorism preparations ahead of the 2020 Tokyo Olympics and other major international events, it has been learned.

The measure could take force as early as June and is designed to prevent terrorists from entering Japan, informed sources said Friday. On top of the sporting spectacle, Japan is slated to host a major political summit in 2016.

The data to be ordered from the airlines is known as the passenger name record, or PNR.

The PNR includes basic data, such as names, passport numbers, departure and destination places, plus detailed information including flight booking dates and locations, credit card numbers, names of travel companions, telephone numbers and email addresses.

Following a revision to the immigration control and refugee recognition law, airlines are required to submit personal data on suspicious passengers if requested by customs or immigration authorities.

In line with the plan to expand PNR coverage to all passengers, the government will promote the digitization of the data, the sources said.

The government, however, may need to address concerns that the measure allows it to collect private information. The balance between privacy and security has been hotly debated in Europe, which is also boosting antiterrorism measures.