It had launched a joint bid for the company with French insurer Axa, which already owns a 54 per cent stake in AXA APH.
But National Australia Bank (NAB) has launched a rival bid worth $12 billion to take control of Axa Asia Pacific Holdings.
It has offered $5.71 a share for the firm, higher than a rival bid of $5.52 from and AMP and Axa.
NAB's offer is contingent on Axa getting to increase its stake by the level it wanted, leaving AMP out in the cold.
The offer, which will see NAB take on AXA AMP's operation in Australia and New Zealand, while leaving its Asian operations to Axa, has been given the thumbs-up by independent directors at AXA AMP.
Last month, NAB chief executive Cameron Clyne said that his company, which currently owns two banks in the UK, will either expand its operations in Britain or leave it completely.
By Claire Archer