Parties paused for a minute of silence an hour before midnight Wednesday, with the famed Sydney Harbour Bridge bathed in white light to symbolise peace.
The Mossad intelligence agency of Israel, Iran's regional archfoe, the same day said on social media it was "with you on the ground" in a message to Iranian protesters.
Ahead of the festivities, Germany and Australia issued travel warnings for Turkey, urging their nationals to exercise caution due to "the threat of terrorism".