EBay Inc. said on Tuesday it would buy Giosis Pte. Ltd.'s Japanese business, including the Qoo10 online shopping platform, to expand its presence in Asia's second-largest economy.

Giosis, which already counts eBay as an investor, operates seven localized online marketplaces in five countries, including Japan and Singapore.

U.S.-based eBay said it would relinquish its stake in Giosis' non-Japanese businesses.

Devin Wenig, eBay's chief executive officer, said in an interview with Reuters the company expects significant growth in Japan, already the world's third-largest e-commerce market.

"There is this perfect convergence of growing wealth and technology adoption," Wenig said. "We think there's a lot of runway."

The deal will bring eBay's technology and its worldwide sellers to Qoo10's base of 2 million shoppers, mirroring its play book in South Korea nearly a decade ago, Wenig said.

"We're going to bring the world's inventory into Japan," he said.

Wenig declined to disclose the terms of the deal, valued at close to $700 million, according to a Bloomberg report.

EBay has modified its platforms, including its namesake shopping service, to include grouped listings and a simpler payment process to lure shoppers amid stiff competition from Amazon.com Inc.

Shares in eBay are up about 14 percent this year.