New Zealand could soon have its second formal ally, as the Government considers joining Australia and Fiji's defence pact.

Anthony Albanese and Sitiveni Rabuka inked the deal on Monday, promising to come to each other's defence in an attack. 

Prime Minister Chris Luxon's confirmed Cabinet's pondering signing up, and he's spoken to both leaders about it. 

Newstalk ZB senior political correspondent Barry Soper explained what we know so far.

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