NHK has learned that the operator of a popular app used for buying and selling goods in Japan is expected to be listed on the Tokyo Stock Exchange.

Mercari could make its debut on the TSE's section for start-up firms Mothers as early as June this year.

Sources say the company's market capitalization could exceed 200 billion yen, or more than 1.8 billion dollars. That would make it one of the biggest initial public offerings of the year in Japan.

Mercari has been growing rapidly since its launch 5 years ago. It was one of the first in Japan to offer a flea market app for consumers to buy and sell their used items.

The TSE's screening of Mercari has been slow going, due to issues with some of the offerings through its app. A number of users offered to sell cash and other questionable items. But Mercari has stepped up preventive measures, including clarifying sellers' identities.