GRAM has agreed to increase its all-cash offer price to $1.85 per share, which will value PNA shares at approximately $1.2 billion.
All independent PNA directors intend to accept the offer, in the absence of a superior proposal.
The offer represents an eight per cent premium to the initial GRAM offer, which shareholders rejected. It also represents a 51 per cent premium to the last closing price for PNA shares prior to the offer.
Unless a competing proposal emerges, GRAM will not increase its offer price.
PNA chairman Garry Hounsell says this represents the best option for PNA shareholders to "realise premium value at this time for their shares".
"The revised offer enables our shareholders to realise a compelling premium for their shares and provides certain cash value," says Hounsell.
"GRAM has been a supportive shareholder since 2009 and it is encouraging that through the offer they have endorsed the company's strategy as well as the management and employees who ultimately are responsible for making PanAust the high quality company that it is today.
"GRAM is well-placed to support the long-term strategy of the company, including the development of the Frieda River Project in PNG."
The company owns a 24.26 per cent stake in PNA, with this being likely to "significantly increase" if the offer goes through according to PNA's release to the market.
The offer is set to close on 15 May 2015 unless extended.
Help us deliver quality journalism to you.
As a free and independent news site providing daily updates
during a period of unprecedented challenges for businesses everywhere
we call on your support