Kevin Rudd was sworn in as the 26th prime minister of Australia on Monday, nine days after he won the elections that ended over 11 years of conservative rule.
The new Australian cabinet sworn in at Government House in Canberra will also have Julia Gillard as the first woman deputy prime minister of the country.
Rudd, 50, said he hoped Australia could ratify the Kyoto Protocol in a week's time, a major policy shift from his predecessor John Howard-led coalition government, isolating the US as the only industrialised country not to have ratified the greenhouse reduction treaty.
As the two-week United Nations Framework Convention on Climate Change conference opens in Bali on Monday, Rudd said: "There are processes concerning the instruments of ratification and when they are lodged with the United Nations, but we would hope to have that done very, very soon - ideally within the course of the next week or so."
Rudd along with his new ministers - Minister for Climate Change Penny Wong, Environment Minister Peter Garrett and Treasurer Wayne Swan will be in Bali to sign the mandate.
The new ministry comprising 10 cabinet ministers, an outer ministry of 20 and 12 parliamentary secretaries were also sworn-in.
At the swearing-in ceremony, Governor-General Jeffery said: "With a clear majority of members in the House of Representatives, Prime Minister Rudd and his government are now charged with the responsibility to implement its election policies and in the process to govern for all Australians."
Rudd's wife Therese Rein and three children were present at the ceremony.