National Australia Bank will not face any opposition from New Zealand authorities in its bid for AXA Asia Pacific's Australasian businesses as it enters the last two weeks to win over Australia's anti-trust regulator.

New Zealand's Overseas Investment Office cleared NAB to buy the AXA units, saying it met criteria for investment in significant business assets. NAB said the acquisition would help grow its wealth management business "so as to deliver the best possible products to clients and advisers within both Australia and New Zealand."

That comes after the Commerce Commission said "there would only be a minimal degree of aggregation of market share" if NAB acquired the AXA businesses, in its approval report for rival AMP to buy the wealth management business.

AMP and NAB have been battling it out to buy AXA's Australian and New Zealand businesses, and AMP pulled ahead after the Australian Competition & Consumer Commission turned down NAB's superior bid saying the bank's wrap platform would limit competition in the market.

Since then, NAB is engaging with interested parties over the sale of AXA's North investment platform in an attempt to placate the ACCC.

Earlier this month, NAB extended its framework deed with AXA AP's French parent, AXA SA until July 15, the deadline for the anti-trust regulator to make a final decision on the matter.