Korean conglomerate Hanwha has formally abandoned its pursuit of Austal, the only ASX-listed shipbuilder, accusing the company of making it impossible to conduct due diligence ahead of a binding takeover bid.

In a letter to Austal obtained by The Australian Financial Review, Hanwha chief executive Hyek Woong Kwon accused the company of agreeing to provide access to its operations but later cancelling them “without prior notice or explanation two days before the visits were scheduled”.