The National Australia Bank is persisting with its attempts to buy AXA Asia Pacific Holdings, in the face of its continuing inability to get a deal that will make the competition regulator, the ACCC, happy.

AXA AP and its parent AXA SA revealed yesterday that they have agreed with the NAB to extend a $13.3 billion acquisition agreement until August 31 while the NAB seeks to address regulatory concerns.

AXA Asia Pacific said NAB continues to pursue options to meet the Australian Competition and Consumer Commission's concerns over the deal.

The regulator blocked the deal on April 19 citing lack of competition in retail investment platforms.

The three companies have also agreed for AXA to pay an interim dividend of up to 9.25c, if AXA Asia Pacific's board also supports the dividend payment.

The extension has been expected for some days now and yesterday's announcement was not unexpected in its timing.

NAB and AXA have been working since the April 19 rejection to find a solution to ACCC concerns about NAB's bid for AXA APH.

The Commission believes the deal has anti-competitive parts, most notably AXA APH's North wealth platform, and the concentration of market power if NAB acquires AXA APH including North.

It means that an attempt to do a deal with smaller wealth manager, IOOF, with it buying the investment platform called North from AXA/NAB after the bid, plus the funds that are managed through the platform (said to be around $40 million) remain uncompleted, or inadequate in some way.

Last Thursday, NAB said negotiations over a potential sale of AXA APH's North Wealth platform still were progressing.

ACCC approval is not an option for the AMP, which was the underbidder for AXA AP.

AXA AP shares fell 8c yesterday to $5.17, as they continue to trade in a holding pattern.

NAB shares were off 44c at $24.05.