Photo/IllutrationChief Cabinet Secretary Yoshihide Suga, second from right, listens to views on the new imperial era name from the heads and deputy heads of the two chambers of the Diet on April 1. (Takayuki Kakuno)

Mobile phones had to be handed over beforehand, meeting rooms were screened for bugging equipment and participants were, in effect, held hostage until Chief Cabinet Secretary Yoshihide Suga announced the name of the new imperial era.

Government officials were determined to prevent the name Reiwa leaking prior to the announcement shortly before noon on April 1.

The name will take effect from May 1, when Crown Prince Naruhito ascends the Chrysanthemum Throne following the abdication of his father, Emperor Akihito, the day before.

Prior to the start of the series of meetings on April 1 to pick the new imperial era name, government officials checked rooms for bugs behind desks and in potted plants.

The nine individuals who convened from 9:30 a.m. to discuss the candidate names not only turned over their mobile phones before the start of the meeting, but also had to return documents distributed ahead of an explanation given by Kazuhiro Sugita, a deputy chief Cabinet secretary.

The meeting lasted about 40 minutes, and the participants were required to remain in a room at the prime minister's office until all formalities had been observed, culminating in the release of the name to the public at large via TV broadcasts.

The panel members were allowed to leave around noon after Suga announced the era name.

Nobel Prize laureate Shinya Yamanaka, one of the participants, was not surprised by the high level of secrecy, noting that members of the committees selecting Nobel Prize winners each year also turn over their mobile phones beforehand.

Similar steps were taken for Cabinet ministers prior to their meeting to agree on a name.

Once the committee meeting wound up, Suga visited the official residence of the Lower House speaker to discuss the issue with the heads and deputy heads of the two Diet chambers.

During those discussions, Lower House Vice Speaker Hirotaka Akamatsu expressed displeasure at being asked beforehand to cooperate in maintaining a veil of secrecy over the new name until the official announcement. He asked for a retraction of the request on grounds it would set a bad precedent.

Suga apologized and retracted the request.

Lower House Speaker Tadamori Oshima intervened and the four lawmakers did not have to turn over their mobile phones. To make it easier to isolate the four from the outside world, they were asked to dine together at Oshima's official residence, thereby ensuring secrecy would be maintained.

Later that day, Prime Minister Shinzo Abe explained on a TV news program why such secrecy was required.

"It was important to ensure that everyone learned (of the new era name) at the same time through the official announcement, and that required strict control of information," he said.