EBay Inc has agreed to buy a controlling stake in South Korean online retailer Gmarket Inc for $413 million, at a 32.5 percent premium, news service eDaily reported on Monday.

The long-discussed deal would help U.S. online auctioneer eBay emerge as a dominant player in South Korea's customer-to-customer online market by taking control of its key competitor.

EBay would buy a 34.2 percent stake in Gmarket from its current top shareholder Interpark and the Korean firm's chairman, at $24 a share, eDaily reported, citing unidentified sources.

Spokesmen at Gmarket and Interpark could not confirm the report.

The reported price compares with Gmarket's latest closing of $18.12 a share. The final contract would be signed on Wednesday, eDaily said.

Nasdaq-listed Gmarket runs customer-to-customer marketplaces and has more than 10 million registered users in South Korea. It competes with eBay's South Korean unit, Internet Auction Co.

EBay has won conditional approval from South Korea's antitrust watchdog on the Gmarket deal. When combined, Gmarket and Internet Auction would have 87 percent of the country's online customer-to-customer market.

Shares of Interpark had risen 4.8 percent as of 0129 GMT, leading the junior Kosdaq market's 2.6 percent rise.

(Reporting by Rhee So-eui; Editing by Ken Wills)