Shareholders in navy shipbuilder Austal say they want the board to at least grant due diligence to South Korea’s Hanwha Group to better Austal’s chances of extracting an improved takeover bid.

The takeover target dismissed a $1 billion offer from Hanwha at $2.825 cash a share on April 2 on the basis that it was unlikely to secure the necessary regulatory approvals. But Defence Minister Richard Marles last week volunteered that the Albanese government has no concerns with a Hanwha bid.