UPDATE 1-Stockland sells NZ retail assets for A$322 million

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SYDNEY, Dec 24 (Reuters) - Australian property developer Stockland Group Ltd (SGP.AX) said on Monday it had sold its 50 percent stake in three New Zealand shopping centres to AMP New Zealand Property Retail Ltd for A$322 million ($280 million).

Stockland said selling its stake in the Auckland-based centres, which it jointly owned with AMP New Zealand Property Retail, came as it looked at opportunities in Australia and the UK.

Stockland Retail Chief Executive John Schroder said in a statement the sale was at a strong premium to book value.

Stockland, which owns more than A$10 billion of housing estates, shopping centres and office buildings, made its first acquisition outside Australia and New Zealand in February when it bought the Halladale Group, a UK property development and investment company, for 171 million pounds.

AMP Property Portfolio is a private investor in retail and office buildings, and is wholly owned by Australia's AMP Ltd (AMP.AX), New Zealand's largest fund manager.

Stephen Costley, General Manager of AMP Property Portfolio said in a separate statement the acquisition was part of a strategy to re-weight the portfolio following the takeover of Capital Properties New Zealand Limited in 2006. ($1=A$1.15) (Reporting by Ben Wilson)