PNG's state enterprise minister Ben Micah told parliament that the Pacific Games — held in Port Moresby this month — proved the country could compete on the world stage.
"I think Australia and New Zealand can look level at us and not laugh at us anymore," Mr Micah said.
"[In future] I predict, Mr Speaker, our Kumuls are going to beat the Kangaroos.
"We are going to hunt them down, we'll kill them and we'll eat them."
His comments come weeks after New Zealand weightlifter Douglas Sekone-Fraser withdrew from the Pacific Games after posting two photos on Instagram referring to locals as "cannibals".
One photo was a selfie and the other showed PNG dancers in ceremonial dress before the opening ceremony and included the hashtag #cannibals. They were later deleted.
The gaff sparked outrage on social media for promoting an outdated image of PNG and Sekone-Fraser was sent home.
The Pacific Games ended on Saturday and was widely seen as a success in a city better known for crime and violence.