The name of the upcoming Imperial era, Reiwa, was added to the list of candidates after mid-March during the last stage of the government's selection process, according to sources.

The number of era name proposals stood between 20 and 30 as of late January before Chief Cabinet Secretary Yoshihide Suga started the process of narrowing down the list, the sources said Wednesday.

As of early March, Reiwa was still not on the list, and it apparently emerged after Suga on March 14 officially asked experts of Japanese literature, Chinese literature, Japanese history and East Asian history to come up with more proposals, the sources said.