JFE Holdings Inc. and IHI Corp. will discuss combining their shipbuilding operations to create Japan's biggest shipyard, challenging South Korean and Chinese rivals.

The Tokyo-based firms will discuss the details, including the merger ratio, at a later date, according to a joint statement released Tuesday. IHI said its board will consider combining wholly owned unit IHI Marine United Inc. with JFE's 85 percent-controlled Universal Shipbuilding Corp. subsidiary.

The merger would create the world's sixth-largest shipbuilder, with annual sales of ¥345 billion, behind South Korean rivals, including Hyundai Heavy Industries Co.