BNZ will be back in the wealth management game in a big way if its parent company National Australia Bank’s surprise deal to buy Axa Asia Pacific goes through.

Earlier this week AMP and Paris-based Axa SA, which owns 53% of Axa Asia Pacific, boosted their offer for Axa Asia Pacific from A5.34 to A$6.22 per share, putting the company’s value at A$12.85 billion.

But NAB has come from nowhere with a bigger bid, announcing yesterday it had agreed to a deal to buy Axa Asia Pacific’s Australia and New Zealand assets for A$13.29 billion.

A complex offer from AMP for Axa’s Australian and New Zealand businesses has been rejected by Axa Asia Pacific (APH), which says the proposal “seriously undervalued” the company.

AMP shares were placed in a trading halt on the NZX this morning as details of the offer leaked out before the official announcement.

AMP and Axa’s French parent Axa SA had worked together on the proposed deal, which would have seen AMP buy out Axa APH, then sell the Asian part of its business back to Axa SA.