J-pop stars Tomohisa Yamashita and Kazuya Kamenashi have been disciplined by their agency after they were spotted drinking with two underage girls.

Johnny & Associates announced on Monday (Aug 17) that Yamashita, 35, has been suspended from showbiz activities for an unspecified period of time, while Kamenashi, 34, was given a stern warning and required to write a letter to reflect on his actions.

According to Japanese newspaper Mainichi Shimbun, the agency felt that the pair's actions during the coronavirus pandemic "lacked awareness and responsibility".

Japanese magazine Shukan Bunshun reported on Aug 7 that Yamashita, who recently acted in the thriller series The Head, and Kamenashi, a member of boyband Kat-tun, went drinking at a bar in Tokyo on July 30.

Shukan Bunshun said there were several other people at the bar with the two girls. The magazine said one of the girls is a 17-year-old student who is also a part-time model. The other girl is 18.

The legal drinking age in Japan is 20.

In response to the reports, Johnny & Associates admitted in a statement that both Yamashita and Kamenashi were drinking with underage girls at the time. The agency said both artists were not aware of the real ages of the girls, as they were introduced to them by other friends at the bar.

The agency did not react to Shukan Bunshun's report that Yamashita was seen at the same hotel with the 17-year-old girl after the drinking session.

Johnny & Associates have previously suspended Hikaru Iwamoto, leader of idol group Snow Man, and Keiichiro Koyama, leader of Japanese band News, for drinking with underage girls.