The Prime Minister, John Key, and his wife Bronagh are spending the night at the private home of his Australian counterpart, Malcolm Turnbull.
The Australian prime minister has two official residences, the Lodge in Canberra and Kirribilli House in Sydney.
But Mr Turnbull is hosting Mr and Mrs Key at his own home in Point Piper, an affluent harbourside suburb of eastern Sydney.
Australian media have reported that it is unprecedented for an Australian prime minister to host a visiting leader at their own home.