Ebay on Thursday unveiled its plans to take over Gmarket, a South Korean auction site, for $1.2bn as part of a move by the US group to accelerate its push into Asia as its core home business suffers.

The purchase of Gmarket, which is listed on Nasdaq and has more than 18m registered users in South Korea, will make Ebay a dominant force in the country’s vibrant e-commerce market and give it a springboard for expansion into other parts of Asia, where the company has a relatively weak presence.