Zarif is in Australia at the last leg of his Asian and Oceania tour that started March 5.
He used the occasion of his visit to the country to plant a tree which will stand as the symbol of friendship between Iran and Australia.
Australia's interior minister accompanied Zarif during the program.
Earlier in the day, he visited the Australian parliaemnt to brief its members on the Joint Comprehensive Plan of Action (JCPOA).
They also reviewed ways to widen parliamentary relations.
Zarif arrived in the Austrian capital on Monday.