Justin Trudeau has been sworn in as Canada's 23rd prime minister and introduced a cabinet he says "looks like Canada."

Making his first public address as prime minister on the steps of the majestic Rideau Hall in Ottawa, Trudeau said his new government will work to earn the trust of Canadians through sound policy-making, better decisions and a strong vision.

Surrounded by his 30 new cabinet ministers, he said the ministry showcases Canada's talent and diversity.

"Canadians elected extraordinary Canadians from across this country and I am glad I've been able to highlight a few of them in this cabinet here with me today," he said.

Asked why it was important to have gender parity in this cabinet, Trudeau said simply: "Because it's 2015."

Trudeau said he hopes to recall Parliament in early December, but will discuss timing with his cabinet before confirming a date. His first legislative priority is to lower taxes for middle-income Canadians and raise taxes for the top one per cent of income earners.

With an international summit on climate change in Paris set to begin Nov. 30, Trudeau also said Canada will be a "strong and positive actor" on the world stage, working with provinces, municipalities and global partners.

He also said he plans to take a collaborative approach to governing to find solutions in the best interests of Canadians.

"This is going to be a period of slight adjustment in the political world in Canada, because government by cabinet is back," he said.

After arriving this morning at Rideau Hall in Ottawa, arm in arm with his wife Sophie Grégoire, Trudeau unveiled a smaller cabinet that puts political newcomer Bill Morneau in charge of the critical finance portfolio.

Justin Trudeau asked about gender parity in cabinet 1:13

Trudeau's front bench will include a mix of fresh faces and political veterans, and fulfils his promise to have an even number of men and women.

Jody Wilson-Raybould, a former B.C. regional First Nations chief who will preside over the justice file, was choked with emotion as she was sworn in to office.

Harjit Sajjan was a surprise pick as the new minister of national defence. He was a lieutenant-colonel in the Canadian Armed Forces and a combat veteran who has served in Bosnia-Herzegovina and completed three separate deployments to Afghanistan.

His associate minister Kent Hehr, who is also the new minister for veterans' affairs, is a former lawyer and popular former Alberta MLA. He was the victim of a 1991 drive-by shooting that left him paraplegic.

Outside Rideau Hall, hundreds of people lined the walkway amid brilliant fall colours on an unseasonably warm morning to watch the ceremony on large screens assembled on the lawns. Inside, the ceremony featured two young Inuit throat singers, a First Nations drum dance and wrapped up with a lively Métis Prairie fire dance.

Their performances prompted smiles and applause, including from the newly minted prime minister.

Samantha Metcalfe and Cailyn Degrandpre of Ottawa broke into giggles following their performance 0:54

The new ministry shakes up some of the former cabinet configuration, with a new science portfolio and the renaming of others, including a families, children and social development department.

Rookie MPs in other key roles named Wednesday in Ottawa include:

Mélanie Joly, a Montreal lawyer, who will be in charge of Canadian heritage.

Catherine McKenna, an Ottawa lawyer, becomes environment and climate change minister.

Jane Philpott, a family physician, becomes health minister.

Trudeau has also included a number of political veterans.

Stéphane Dion takes on the powerful foreign affairs post as Trudeau prepares to attend a series of international meetings. Ralph Goodale becomes public safety minister, while Marc Garneau becomes transport minister and Chrystia Freeland is the new international trade minister.

Other high-profile names were left off the list, including former Toronto police chief Bill Blair and Andrew Leslie, a retired Canadian Forces lieutenant-general who served as chief of transformation and earlier as chief of the land staff.

Tonight on The National

Tune in tonight as The National goes behind the scenes with Justin Trudeau. It's the inside story of his first day as prime minister. Peter Mansbridge and a CBC crew were given exclusive and unprecedented access as Trudeau prepared to be sworn in and as he met with his new government afterward.

The special edition of The National airs at 9 p.m. ET on CBC News Network, 10 p.m. on CBC television, 10:30 p.m. in Newfoundland.

PM to keep 'focused on the people'

Trudeau issued a statement touting the strengths of his team and promising to rebuild relations with indigenous Canadians and run an open, ethical and transparent government.

Justin Trudeau greets the crowd outside Rideau Hall after being sworn in as Canada's 23rd Prime Minister Wednesday. (Giacomo Panico/CBC)

"We will shine more light on government to ensure it remains focused on the people it is meant to serve," he said. "Openness and transparency will be our constant companions, and we will work to restore Canadians' trust in their government and in our democracy. We are committed to the highest ethical standards and applying the utmost care in the handling of public funds."

U.S. Ambassador to Canada Bruce Heyman offered congratulations to the new cabinet.

"I look forward to getting to know each of them and working with them in their new portfolios as we continue to enhance the close relationship between our two nations," he said in a statement.

Outgoing prime minister Stephen Harper formally submitted his resignation in a brief meeting with the Governor General at 9:26 a.m. ET in Rideau Hall, according to a release from the Governor General's Office.

"It's a historic day for women," said Sheila Copps, a long-time Liberal cabinet minister and deputy prime minister to Jean Chrétien. "Gender parity in the national cabinet is huge. It sends a great message to our daughters and sons."

When she first entered provincial politics in 1981, Copps was the only woman in a caucus of 34. She believes that gender parity will ensure "strength in numbers" and change the parliamentary dynamic for the better.

Members of the public wait at the gates of Rideau Hall, the Governor General's official residence before Justin Trudeau was sworn in as prime minister. (Justin Tang/Canadian Press)

After the ceremony, Trudeau hosted a Google Hangout with children at five public schools before holding his first cabinet meeting on Parliament Hill.

Keen interest in Trudeau

Ron Stagg, a political historian at Toronto's Ryerson University, expects the keen interest in Trudeau will continue in Canada and abroad because he is young, projects a positive image in contrast to his predecessor, and is the son of former prime minister Pierre Elliott Trudeau.

"Part of this expectation stems from the tone set by the campaign and part from the disenchantment of many voters with the Harper government and the negative atmosphere it created in the years of majority government," he said. "One very positive effect of the Liberal versus Conservative polarization is that it has brought youth back into the political process."

The next fixed federal election date is Oct. 21, 2019.

Prime Minister Justin Trudeau stands with Gov. Gen. David Johnston after being sworn in as prime minister at Rideau Hall. (Justin Tang/Canadian Press)

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