The family feud at Japanese-Korean retail giant Lotte Group has intensified as Chairman Shin Dong Bin's older brother attempts to oust him from one of the conglomerate's key companies.

Kwang Yoon-sa will hold a shareholders meeting Wednesday to dismiss Shin from his director position and will hold a board meeting afterward to appoint Lotte founder Shin Kyuk-ho's older son Shin Dong-joo as chief executive officer, according to an emailed statement from the eldest son's company.

Kwang Yoon-sa, based in Japan, is the biggest holder of unlisted Lotte Holdings Co., which is key to controlling conglomerate Lotte Group because of its various stakes in group affiliates.