According to the sources, Lee traveled to Japan last week and visited the headquarters of NTT Docomo Inc. and KDDI Corp., and exchanged ideas over the 5G business with officials from the two mobile carriers.
The meeting occurred as Japan is preparing to launch full-fledged 5G services, which are expected to start next year.
The South Korean tech giant has been making efforts to penetrate deeper into the Japanese market. In October, Samsung decided to join forces with NEC Corp. on developing 5G telecom equipment.
The company also plans to support the 2020 Summer Olympics in Tokyo as a worldwide partner of the International Olympic Committee.
Samsung accounted for 6.8 percent of the Japanese smartphone market in the fourth quarter of 2018, according to industry tracker Canalys. (Yonhap)