TOKYO -- The operators of Yahoo sites in Japan and popular messaging app Line seek to merge into an internet group that spans finance, retail and other services, Nikkei has learned.

SoftBank Group, which owns 45% of Yahoo Japan parent Z Holdings, and South Korea's Naver, which owns 73% of Line, are in the final stage of negotiations, sources said. They aim to reach a basic agreement by the end of the month.

SoftBank Corp., the mobile arm of SoftBank which controls Z Holdings, said in a statement on Thursday morning that it is "discussing various possibilities including [the merger]".

The deal would create a mega-platform with more than 100 million users across financial services, e-commerce and more, reshaping Japan's digital landscape and forming a bigger competitor to American and Chinese internet groups.

The combined entity would overtake Rakuten and Japan's internet company by revenue.

One proposal is for SoftBank and Naver to set up a new 50-50 venture, which would become the top shareholder in Z Holdings. Yahoo and Line would then become separate wholly owned subsidiaries of Z Holdings.

The two sides are in negotiations to make the new venture into a consolidated subsidiary of SoftBank. Z Holdings would remain listed on the Tokyo Stock Exchange.

Around the world, one-stop platforms are taking the place of smaller internet companies that specialize in e-commerce, social media or financial services. A key example is China's Tencent Holdings, which has over 1 billion users across its WeChat app, e-commerce and e-payment platforms, streaming services, games and more. It is now a "superapp," entwined in every aspect of its customers' lives.

Japanese companies are also rushing to become the next superapp.

Line is Japan's most popular chat app with 82 million monthly users, putting it far ahead of both Instagram and Facebook in the country. But it is struggling to gain new users. With revenue of just over 200 billion yen, it lacks the cash to become a superapp on its own, and logged a 33.9 billion yen net loss for the January-September period.

Z Holdings hopes to bolster services like mobile payments, e-commerce and a news-search engine through a merger with Line. Line has similar services and could provide access to the app's users.

The two companies would likely achieve significant synergies in digital payments, a sector that has seen a wave of new entrants in Japan. Line Pay has 37 million users and PayPay, operated jointly by SoftBank and Yahoo Japan, has 19 million.