Australia and PNG will agree to defend each other from military attack as China’s Pacific influence grows

Australia’s prime minister, Anthony Albanese, said the Pukpuk defence treaty with Papua New Guinea was about mutual security and sovereignty. Photograph: Mick Tsikas/AAP

Australia and Papua New Guinea will agree to defend each other in the event of a military attack, part of a landmark defence agreement due to be signed on the sidelines of celebrations to commemorate the country’s independence this week.

Anthony Albanese and PNG’s defence minister, Billy Joseph, both downplayed a delay to the deal being formalised, insisting the plan known as a Pukpuk treaty won’t affect sovereignty in the former Australian colony.